diff --git a/.travis.yml b/.travis.yml
index bd2a64415..aa10d1193 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,5 @@
 language: python
 python:
-  - '2.7'
   - '3.5'
   - '3.6'
   - '3.7'
diff --git a/README.rst b/README.rst
index bd6bdde52..90bd2416f 100644
--- a/README.rst
+++ b/README.rst
@@ -17,7 +17,7 @@ is used as a central point of communication between all components.
 Modoboa is developed with modularity in mind, expanding it is really
 easy. Actually, all current features are extensions.
 
-It is written in Python and uses the `Django
+It is written in Python 3 and uses the `Django
 <https://www.djangoproject.com>`_, `jQuery <http://jquery.com>`_ and
 `Bootstrap <http://getbootstrap.com/>`_
 frameworks.
@@ -68,4 +68,4 @@ The following external libraries are provided with Modoboa:
 .. |codecov| image:: http://codecov.io/github/modoboa/modoboa/coverage.svg?branch=master
    :target: http://codecov.io/github/modoboa/modoboa?branch=master
 .. |codacy| image:: https://api.codacy.com/project/badge/Grade/82fd10127ac3468899ca75f04e9862b6
-    :target: https://www.codacy.com/app/modoboa/modoboa?utm_source=github.com&amp;utm_medium=referral&amp;utm_content=modoboa/modoboa&amp;utm_campaign=Badge_Grade
\ No newline at end of file
+    :target: https://www.codacy.com/app/modoboa/modoboa?utm_source=github.com&amp;utm_medium=referral&amp;utm_content=modoboa/modoboa&amp;utm_campaign=Badge_Grade
diff --git a/bin/modoboa-admin.py b/bin/modoboa-admin.py
index 78de64d39..53bf9ac8e 100644
--- a/bin/modoboa-admin.py
+++ b/bin/modoboa-admin.py
@@ -1,7 +1,4 @@
 #!/usr/bin/env python
-# coding: utf-8
-
-from __future__ import unicode_literals
 
 from modoboa.core.commands import handle_command_line
 
diff --git a/doc/manual_installation/webserver.rst b/doc/manual_installation/webserver.rst
index 8f528fb88..648f4bb38 100644
--- a/doc/manual_installation/webserver.rst
+++ b/doc/manual_installation/webserver.rst
@@ -50,7 +50,7 @@ This is just one possible configuration.
 To use mod_wsgi daemon mode, add the two following directives just
 under ``WSGIScriptAlias``::
 
-  WSGIDaemonProcess example.com python-path=<modoboa_instance>:<virtualenv path>/lib/python2.7/site-packages
+  WSGIDaemonProcess example.com python-path=<modoboa_instance>:<virtualenv path>/lib/python3.7/site-packages
   WSGIProcessGroup example.com
 
 Replace values between ``<>`` with yours. If you don't use a
diff --git a/modoboa/__init__.py b/modoboa/__init__.py
index ad361c484..4044639f7 100644
--- a/modoboa/__init__.py
+++ b/modoboa/__init__.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Modoboa - Mail hosting made simple."""
 
-from __future__ import unicode_literals
-
 from pkg_resources import DistributionNotFound, get_distribution
 
 try:
diff --git a/modoboa/admin/__init__.py b/modoboa/admin/__init__.py
index 80f7ae2d3..4002eb9dd 100644
--- a/modoboa/admin/__init__.py
+++ b/modoboa/admin/__init__.py
@@ -1,5 +1 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 default_app_config = "modoboa.admin.apps.AdminConfig"
diff --git a/modoboa/admin/api.py b/modoboa/admin/api.py
index 3ca68504b..dd74ecf10 100644
--- a/modoboa/admin/api.py
+++ b/modoboa/admin/api.py
@@ -1,14 +1,10 @@
-# -*- coding: utf-8 -*-
-
 """Admin API."""
 
-from __future__ import unicode_literals
-
 from django import http
 from django.contrib.contenttypes.models import ContentType
 
 from rest_framework import filters, status, viewsets
-from rest_framework.decorators import detail_route, list_route
+from rest_framework.decorators import action
 from rest_framework.exceptions import ParseError
 from rest_framework.permissions import DjangoModelPermissions, IsAuthenticated
 from rest_framework.response import Response
@@ -86,7 +82,7 @@ class AccountViewSet(viewsets.ModelViewSet):
             queryset = queryset.filter(mailbox__domain__name=domain)
         return queryset
 
-    @detail_route(methods=["put"])
+    @action(methods=["put"], detail=True)
     def password(self, request, pk=None):
         """Change account password."""
         try:
@@ -100,7 +96,7 @@ class AccountViewSet(viewsets.ModelViewSet):
         return Response(
             serializer.errors, status=status.HTTP_400_BAD_REQUEST)
 
-    @list_route()
+    @action(detail=False)
     def exists(self, request):
         """Check if account exists.
 
diff --git a/modoboa/admin/app_settings.py b/modoboa/admin/app_settings.py
index 8b343910a..c2618e64e 100644
--- a/modoboa/admin/app_settings.py
+++ b/modoboa/admin/app_settings.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Modoboa admin settings."""
 
-from __future__ import unicode_literals
-
 import os
 
 from django import forms
diff --git a/modoboa/admin/apps.py b/modoboa/admin/apps.py
index 77ba62271..e39753524 100644
--- a/modoboa/admin/apps.py
+++ b/modoboa/admin/apps.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """AppConfig for admin."""
 
-from __future__ import unicode_literals
-
 from django.apps import AppConfig
 
 from .app_settings import load_admin_settings
diff --git a/modoboa/admin/constants.py b/modoboa/admin/constants.py
index 623d9b6b5..bfedf1eed 100644
--- a/modoboa/admin/constants.py
+++ b/modoboa/admin/constants.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Admin constants."""
 
-from __future__ import unicode_literals
-
 from django.utils.translation import ugettext_lazy as _
 
 DNSBL_PROVIDERS = [
diff --git a/modoboa/admin/factories.py b/modoboa/admin/factories.py
index e0d5780c8..cadd4907f 100644
--- a/modoboa/admin/factories.py
+++ b/modoboa/admin/factories.py
@@ -1,11 +1,7 @@
-# -*- coding: utf-8 -*-
-
 """
 Fixtures factories.
 """
 
-from __future__ import unicode_literals
-
 import factory
 
 from modoboa.core.factories import PermissionFactory, UserFactory
diff --git a/modoboa/admin/forms/__init__.py b/modoboa/admin/forms/__init__.py
index bb1ded79a..e5cc34c9d 100644
--- a/modoboa/admin/forms/__init__.py
+++ b/modoboa/admin/forms/__init__.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 from .account import (
     AccountForm, AccountFormGeneral, AccountFormMail, AccountPermissionsForm,
     AccountWizard
diff --git a/modoboa/admin/forms/account.py b/modoboa/admin/forms/account.py
index 644ddabec..66935db14 100644
--- a/modoboa/admin/forms/account.py
+++ b/modoboa/admin/forms/account.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Forms related to accounts management."""
 
-from __future__ import unicode_literals
-
 from collections import OrderedDict
 from functools import reduce
 
diff --git a/modoboa/admin/forms/alias.py b/modoboa/admin/forms/alias.py
index 09ee606e4..3a5238ac6 100644
--- a/modoboa/admin/forms/alias.py
+++ b/modoboa/admin/forms/alias.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Forms related to aliases management."""
 
-from __future__ import unicode_literals
-
 from collections import OrderedDict
 
 from django import forms
diff --git a/modoboa/admin/forms/domain.py b/modoboa/admin/forms/domain.py
index 6a05eba45..7e2a6a95d 100644
--- a/modoboa/admin/forms/domain.py
+++ b/modoboa/admin/forms/domain.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Forms related to domains management."""
 
-from __future__ import unicode_literals
-
 from functools import reduce
 
 from django import forms
diff --git a/modoboa/admin/forms/export.py b/modoboa/admin/forms/export.py
index 1a295c599..ca1a46c14 100644
--- a/modoboa/admin/forms/export.py
+++ b/modoboa/admin/forms/export.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 from django import forms
 from django.utils.translation import ugettext_lazy
 
diff --git a/modoboa/admin/forms/forward.py b/modoboa/admin/forms/forward.py
index b270fb32d..5cd7b1b7c 100644
--- a/modoboa/admin/forms/forward.py
+++ b/modoboa/admin/forms/forward.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Forms related to forwards management."""
 
-from __future__ import unicode_literals
-
 from django import forms
 from django.core import validators
 from django.utils.translation import ugettext_lazy
diff --git a/modoboa/admin/forms/import_.py b/modoboa/admin/forms/import_.py
index db50913ff..e598658e7 100644
--- a/modoboa/admin/forms/import_.py
+++ b/modoboa/admin/forms/import_.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Forms related to import operations."""
 
-from __future__ import unicode_literals
-
 from django import forms
 from django.utils.translation import ugettext_lazy
 
diff --git a/modoboa/admin/handlers.py b/modoboa/admin/handlers.py
index 2159f5dd8..f73996c71 100644
--- a/modoboa/admin/handlers.py
+++ b/modoboa/admin/handlers.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Django signal handlers for admin."""
 
-from __future__ import unicode_literals
-
 from django.contrib.contenttypes.models import ContentType
 from django.db.models import signals
 from django.dispatch import receiver
diff --git a/modoboa/admin/lib.py b/modoboa/admin/lib.py
index f2ac6f556..3fe459e66 100644
--- a/modoboa/admin/lib.py
+++ b/modoboa/admin/lib.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Internal library for admin."""
 
-from __future__ import unicode_literals
-
 import ipaddress
 import logging
 import random
diff --git a/modoboa/admin/management/commands/handle_mailbox_operations.py b/modoboa/admin/management/commands/handle_mailbox_operations.py
index 15d8f6e11..b7d9c3b99 100644
--- a/modoboa/admin/management/commands/handle_mailbox_operations.py
+++ b/modoboa/admin/management/commands/handle_mailbox_operations.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """A management command to apply mailbox operations."""
 
-from __future__ import print_function, unicode_literals
-
 import logging
 import os
 import shutil
diff --git a/modoboa/admin/management/commands/modo.py b/modoboa/admin/management/commands/modo.py
index b4f3495f5..94c7e6482 100644
--- a/modoboa/admin/management/commands/modo.py
+++ b/modoboa/admin/management/commands/modo.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Modoboa main management command."""
 
-from __future__ import unicode_literals
-
 from subcommand.base import SubcommandCommand
 
 from .subcommands._export import ExportCommand
diff --git a/modoboa/admin/management/commands/subcommands/_export.py b/modoboa/admin/management/commands/subcommands/_export.py
index 947f81d37..91c40d929 100644
--- a/modoboa/admin/management/commands/subcommands/_export.py
+++ b/modoboa/admin/management/commands/subcommands/_export.py
@@ -1,24 +1,14 @@
-# -*- coding: utf-8 -*-
-
 """Django management command to export admin objects."""
 
-from __future__ import unicode_literals
-
-import sys
+import csv
 
 from django.core.management.base import BaseCommand
-from django.utils import six
 from django.utils.encoding import smart_text
 
 from modoboa.core.extensions import exts_pool
 from modoboa.core.models import User
 from .... import models
 
-if six.PY2:
-    from backports import csv
-else:
-    import csv
-
 
 class ExportCommand(BaseCommand):
     """Command class."""
diff --git a/modoboa/admin/management/commands/subcommands/_import.py b/modoboa/admin/management/commands/subcommands/_import.py
index a202fe22b..d4b7054db 100644
--- a/modoboa/admin/management/commands/subcommands/_import.py
+++ b/modoboa/admin/management/commands/subcommands/_import.py
@@ -1,9 +1,6 @@
-# -*- coding: utf-8 -*-
-
 """Django management command to import admin objects."""
 
-from __future__ import unicode_literals
-
+import csv
 import io
 import os
 
@@ -12,7 +9,6 @@ from chardet.universaldetector import UniversalDetector
 
 from django.core.management.base import BaseCommand, CommandError
 from django.db import transaction
-from django.utils import six
 from django.utils.translation import ugettext as _
 
 from modoboa.core import models as core_models
@@ -20,11 +16,6 @@ from modoboa.core.extensions import exts_pool
 from modoboa.lib.exceptions import Conflict
 from .... import signals
 
-if six.PY2:
-    from backports import csv
-else:
-    import csv
-
 
 class ImportCommand(BaseCommand):
     """Command class."""
@@ -35,7 +26,7 @@ class ImportCommand(BaseCommand):
     def add_arguments(self, parser):
         """Add extra arguments to command."""
         parser.add_argument(
-            "--sepchar", type=six.text_type, default=";",
+            "--sepchar", type=str, default=";",
             help="Separator used in file.")
         parser.add_argument(
             "--continue-if-exists", action="store_true",
@@ -45,7 +36,7 @@ class ImportCommand(BaseCommand):
             "--crypt-password", action="store_true",
             default=False, help="Encrypt provided passwords.")
         parser.add_argument(
-            "files", type=six.text_type, nargs="+", help="CSV files to import.")
+            "files", type=str, nargs="+", help="CSV files to import.")
 
     def _import(self, filename, options, encoding="utf-8"):
         """Import domains or identities."""
@@ -121,10 +112,7 @@ class ImportCommand(BaseCommand):
                             encoding=detector.result["encoding"]
                         )
                 except UnicodeDecodeError as exc:
-                    six.raise_from(
-                        CommandError(
-                            _("Unable to decode CSV file using %(encoding)s "
-                              "encoding") % detector.result
-                        ),
-                        exc
-                    )
+                    raise CommandError(
+                        _("Unable to decode CSV file using %(encoding)s "
+                          "encoding") % detector.result
+                    ) from exc
diff --git a/modoboa/admin/management/commands/subcommands/_manage_dkim_keys.py b/modoboa/admin/management/commands/subcommands/_manage_dkim_keys.py
index c7002c2c0..0bc9e6f4e 100644
--- a/modoboa/admin/management/commands/subcommands/_manage_dkim_keys.py
+++ b/modoboa/admin/management/commands/subcommands/_manage_dkim_keys.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Management command to create DKIM keys."""
 
-from __future__ import print_function, unicode_literals
-
 import os
 
 from django.core.management.base import BaseCommand
diff --git a/modoboa/admin/management/commands/subcommands/_mx.py b/modoboa/admin/management/commands/subcommands/_mx.py
index b88bd30a1..93189a140 100644
--- a/modoboa/admin/management/commands/subcommands/_mx.py
+++ b/modoboa/admin/management/commands/subcommands/_mx.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Management command to check defined domains."""
 
-from __future__ import print_function, unicode_literals
-
 import ipaddress
 
 import gevent
diff --git a/modoboa/admin/management/commands/subcommands/_repair.py b/modoboa/admin/management/commands/subcommands/_repair.py
index 26bfb42f4..7cc8178a6 100644
--- a/modoboa/admin/management/commands/subcommands/_repair.py
+++ b/modoboa/admin/management/commands/subcommands/_repair.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Management command to check and fix known problems."""
 
-from __future__ import print_function, unicode_literals
-
 from django.conf import settings
 from django.core.management.base import BaseCommand
 from django.utils.encoding import smart_str
diff --git a/modoboa/admin/migrations/0001_initial.py b/modoboa/admin/migrations/0001_initial.py
index 9be649089..afa54f6ba 100644
--- a/modoboa/admin/migrations/0001_initial.py
+++ b/modoboa/admin/migrations/0001_initial.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 from django.conf import settings
 
diff --git a/modoboa/admin/migrations/0002_migrate_from_modoboa_admin.py b/modoboa/admin/migrations/0002_migrate_from_modoboa_admin.py
index c854881b6..301a6406b 100644
--- a/modoboa/admin/migrations/0002_migrate_from_modoboa_admin.py
+++ b/modoboa/admin/migrations/0002_migrate_from_modoboa_admin.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/admin/migrations/0003_auto_20151118_1215.py b/modoboa/admin/migrations/0003_auto_20151118_1215.py
index 3dbbfe390..df92da9f4 100644
--- a/modoboa/admin/migrations/0003_auto_20151118_1215.py
+++ b/modoboa/admin/migrations/0003_auto_20151118_1215.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/admin/migrations/0004_auto_20160914_0907.py b/modoboa/admin/migrations/0004_auto_20160914_0907.py
index 32aa5e148..6427b4439 100644
--- a/modoboa/admin/migrations/0004_auto_20160914_0907.py
+++ b/modoboa/admin/migrations/0004_auto_20160914_0907.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.9.9 on 2016-09-14 09:07
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.db.models.deletion
 
diff --git a/modoboa/admin/migrations/0005_auto_20161026_1003.py b/modoboa/admin/migrations/0005_auto_20161026_1003.py
index d679eba6b..a6c94f83c 100644
--- a/modoboa/admin/migrations/0005_auto_20161026_1003.py
+++ b/modoboa/admin/migrations/0005_auto_20161026_1003.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-10-26 08:03
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/admin/migrations/0006_auto_20161104_1900.py b/modoboa/admin/migrations/0006_auto_20161104_1900.py
index daac34e1b..9b48d6b1a 100644
--- a/modoboa/admin/migrations/0006_auto_20161104_1900.py
+++ b/modoboa/admin/migrations/0006_auto_20161104_1900.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-11-04 18:00
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.utils.timezone
 
diff --git a/modoboa/admin/migrations/0007_auto_20161104_1915.py b/modoboa/admin/migrations/0007_auto_20161104_1915.py
index 761a22a12..318e265a4 100644
--- a/modoboa/admin/migrations/0007_auto_20161104_1915.py
+++ b/modoboa/admin/migrations/0007_auto_20161104_1915.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-11-04 18:15
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/admin/migrations/0008_domain_enable_dns_checks.py b/modoboa/admin/migrations/0008_domain_enable_dns_checks.py
index c7be468fe..974d05025 100644
--- a/modoboa/admin/migrations/0008_domain_enable_dns_checks.py
+++ b/modoboa/admin/migrations/0008_domain_enable_dns_checks.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.9.12 on 2017-02-06 06:13
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/admin/migrations/0009_auto_20170215_0948.py b/modoboa/admin/migrations/0009_auto_20170215_0948.py
index b032a7190..262549b50 100644
--- a/modoboa/admin/migrations/0009_auto_20170215_0948.py
+++ b/modoboa/admin/migrations/0009_auto_20170215_0948.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.10.5 on 2017-02-15 08:48
-from __future__ import unicode_literals
-
 from django.db import migrations
 
 
diff --git a/modoboa/admin/migrations/0010_auto_20170215_1328.py b/modoboa/admin/migrations/0010_auto_20170215_1328.py
index e71d408ca..bc4535930 100644
--- a/modoboa/admin/migrations/0010_auto_20170215_1328.py
+++ b/modoboa/admin/migrations/0010_auto_20170215_1328.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.10.5 on 2017-02-15 12:28
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/admin/migrations/0011_domain_transport.py b/modoboa/admin/migrations/0011_domain_transport.py
index 8f037fb6c..001b23761 100644
--- a/modoboa/admin/migrations/0011_domain_transport.py
+++ b/modoboa/admin/migrations/0011_domain_transport.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.10.7 on 2017-12-20 14:17
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.db.models.deletion
 
diff --git a/modoboa/admin/migrations/0012_auto_20180112_1658.py b/modoboa/admin/migrations/0012_auto_20180112_1658.py
index a69e64388..24bc6f938 100644
--- a/modoboa/admin/migrations/0012_auto_20180112_1658.py
+++ b/modoboa/admin/migrations/0012_auto_20180112_1658.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.11.8 on 2018-01-12 15:58
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/admin/migrations/0013_auto_20180124_2311.py b/modoboa/admin/migrations/0013_auto_20180124_2311.py
index d0671ab0d..c5bd1d3b5 100644
--- a/modoboa/admin/migrations/0013_auto_20180124_2311.py
+++ b/modoboa/admin/migrations/0013_auto_20180124_2311.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.11.8 on 2018-01-24 23:11
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/admin/migrations/0014_auto_20181017_1628.py b/modoboa/admin/migrations/0014_auto_20181017_1628.py
index ca7dee0c0..73b47d5b8 100644
--- a/modoboa/admin/migrations/0014_auto_20181017_1628.py
+++ b/modoboa/admin/migrations/0014_auto_20181017_1628.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.11.16 on 2018-10-17 14:28
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/admin/migrations/__init__.py b/modoboa/admin/migrations/__init__.py
index baffc4882..e69de29bb 100644
--- a/modoboa/admin/migrations/__init__.py
+++ b/modoboa/admin/migrations/__init__.py
@@ -1 +0,0 @@
-from __future__ import unicode_literals
diff --git a/modoboa/admin/models/__init__.py b/modoboa/admin/models/__init__.py
index 068fc45e9..29ac0b270 100644
--- a/modoboa/admin/models/__init__.py
+++ b/modoboa/admin/models/__init__.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Admin models."""
 
-from __future__ import unicode_literals
-
 from .alias import Alias, AliasRecipient
 from .base import AdminObject
 from .domain import Domain
diff --git a/modoboa/admin/models/alias.py b/modoboa/admin/models/alias.py
index 98a360c09..fb2d959b4 100644
--- a/modoboa/admin/models/alias.py
+++ b/modoboa/admin/models/alias.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Models related to aliases management."""
 
-from __future__ import unicode_literals
-
 import hashlib
 import random
 
diff --git a/modoboa/admin/models/base.py b/modoboa/admin/models/base.py
index abe182180..8394c3c0d 100644
--- a/modoboa/admin/models/base.py
+++ b/modoboa/admin/models/base.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Base admin models."""
 
-from __future__ import unicode_literals
-
 from django.contrib.contenttypes.fields import GenericRelation
 from django.db import models
 from django.utils import timezone
diff --git a/modoboa/admin/models/domain.py b/modoboa/admin/models/domain.py
index a06932b87..c040ad260 100644
--- a/modoboa/admin/models/domain.py
+++ b/modoboa/admin/models/domain.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Models related to domains management."""
 
-from __future__ import unicode_literals
-
 import datetime
 
 from reversion import revisions as reversion
diff --git a/modoboa/admin/models/domain_alias.py b/modoboa/admin/models/domain_alias.py
index 917039911..055f0ff1e 100644
--- a/modoboa/admin/models/domain_alias.py
+++ b/modoboa/admin/models/domain_alias.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Models related to domain aliases management."""
 
-from __future__ import unicode_literals
-
 from reversion import revisions as reversion
 
 from django.contrib.contenttypes.fields import GenericRelation
diff --git a/modoboa/admin/models/mailbox.py b/modoboa/admin/models/mailbox.py
index ef17ba264..21ede9a5f 100644
--- a/modoboa/admin/models/mailbox.py
+++ b/modoboa/admin/models/mailbox.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Models related to mailboxes management."""
 
-from __future__ import unicode_literals
-
 import os
 import pwd
 
diff --git a/modoboa/admin/models/mxrecord.py b/modoboa/admin/models/mxrecord.py
index 3d2cf9de8..a6f1f518e 100644
--- a/modoboa/admin/models/mxrecord.py
+++ b/modoboa/admin/models/mxrecord.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """MX records storage."""
 
-from __future__ import unicode_literals
-
 import datetime
 
 from django.db import models
diff --git a/modoboa/admin/postfix_maps.py b/modoboa/admin/postfix_maps.py
index 1550fe7e6..026649070 100644
--- a/modoboa/admin/postfix_maps.py
+++ b/modoboa/admin/postfix_maps.py
@@ -1,10 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Map file definitions for postfix."""
 
-from __future__ import unicode_literals
-
-
 class DomainsMap(object):
 
     """Map to list all domains."""
diff --git a/modoboa/admin/serializers.py b/modoboa/admin/serializers.py
index dfd3ed49b..c91382c9a 100644
--- a/modoboa/admin/serializers.py
+++ b/modoboa/admin/serializers.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Admin serializers."""
 
-from __future__ import unicode_literals
-
 from django.conf import settings
 from django.contrib.auth import password_validation
 from django.core.exceptions import ValidationError
diff --git a/modoboa/admin/signals.py b/modoboa/admin/signals.py
index b085d7807..d7e59ba9b 100644
--- a/modoboa/admin/signals.py
+++ b/modoboa/admin/signals.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Modoboa admin signals."""
 
-from __future__ import unicode_literals
-
 import django.dispatch
 
 check_extra_account_form = django.dispatch.Signal(
diff --git a/modoboa/admin/templatetags/admin_tags.py b/modoboa/admin/templatetags/admin_tags.py
index 038eddb21..cc2d36aed 100644
--- a/modoboa/admin/templatetags/admin_tags.py
+++ b/modoboa/admin/templatetags/admin_tags.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Admin extension tags."""
 
-from __future__ import unicode_literals
-
 from functools import reduce
 
 from django import template
diff --git a/modoboa/admin/tests/test_account.py b/modoboa/admin/tests/test_account.py
index 10e43ca6b..86775f6f1 100644
--- a/modoboa/admin/tests/test_account.py
+++ b/modoboa/admin/tests/test_account.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 from unittest import skipIf
 
 from django.test import override_settings
diff --git a/modoboa/admin/tests/test_alias.py b/modoboa/admin/tests/test_alias.py
index b79ed39b6..9bdaf62cd 100644
--- a/modoboa/admin/tests/test_alias.py
+++ b/modoboa/admin/tests/test_alias.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 from django.urls import reverse
 
 from modoboa.core.models import User
diff --git a/modoboa/admin/tests/test_api.py b/modoboa/admin/tests/test_api.py
index 235d6461c..0baf0be38 100644
--- a/modoboa/admin/tests/test_api.py
+++ b/modoboa/admin/tests/test_api.py
@@ -1,11 +1,8 @@
-# -*- coding: utf-8 -*-
-
 """Admin API related tests."""
 
-from __future__ import unicode_literals
-
 import copy
 import json
+from unittest import mock
 
 import dns.resolver
 
@@ -20,13 +17,6 @@ from modoboa.lib.tests import ModoAPITestCase
 from . import utils
 from .. import factories, models
 
-try:
-    # mock is part of the Python (>= 3.3) standard library
-    from unittest import mock
-except ImportError:
-    # fall back to the mock backport
-    import mock
-
 
 class DomainAPITestCase(ModoAPITestCase):
     """Check API."""
diff --git a/modoboa/admin/tests/test_domain.py b/modoboa/admin/tests/test_domain.py
index 0f54ba663..b8a8e9b15 100644
--- a/modoboa/admin/tests/test_domain.py
+++ b/modoboa/admin/tests/test_domain.py
@@ -1,12 +1,9 @@
-# -*- coding: utf-8 -*-
-
 """Domain related test cases."""
 
-from __future__ import unicode_literals
-
 import os
 import shutil
 import tempfile
+from unittest import mock
 
 import dns.resolver
 from testfixtures import compare
@@ -23,13 +20,6 @@ from . import utils
 from .. import factories
 from ..models import Alias, Domain
 
-try:
-    # mock is part of the Python (>= 3.3) standard library
-    from unittest import mock
-except ImportError:
-    # fall back to the mock backport
-    import mock
-
 
 class DomainTestCase(ModoTestCase):
     """Test case for Domain."""
diff --git a/modoboa/admin/tests/test_domain_alias.py b/modoboa/admin/tests/test_domain_alias.py
index d02e4ef96..7559c7d8a 100644
--- a/modoboa/admin/tests/test_domain_alias.py
+++ b/modoboa/admin/tests/test_domain_alias.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 from django.urls import reverse
 
 from modoboa.lib.tests import ModoTestCase
diff --git a/modoboa/admin/tests/test_export.py b/modoboa/admin/tests/test_export.py
index c261520b7..830dd6eab 100644
--- a/modoboa/admin/tests/test_export.py
+++ b/modoboa/admin/tests/test_export.py
@@ -1,12 +1,7 @@
-# -*- coding: utf-8 -*-
-
 """Export related test cases."""
 
-from __future__ import unicode_literals
-
 import sys
-
-from six.moves import StringIO
+from io import StringIO
 
 from django.core.management import call_command
 from django.urls import reverse
diff --git a/modoboa/admin/tests/test_import_.py b/modoboa/admin/tests/test_import_.py
index aa0a5eaad..9ce2e5d88 100644
--- a/modoboa/admin/tests/test_import_.py
+++ b/modoboa/admin/tests/test_import_.py
@@ -1,8 +1,5 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 import os
+from unittest import mock
 
 import dns.resolver
 
@@ -18,13 +15,6 @@ from . import utils
 from .. import factories
 from ..models import Alias, Domain, DomainAlias
 
-try:
-    # mock is part of the Python (>= 3.3) standard library
-    from unittest import mock
-except ImportError:
-    # fall back to the mock backport
-    import mock
-
 
 class ImportTestCase(ModoTestCase):
 
diff --git a/modoboa/admin/tests/test_mailbox_operations.py b/modoboa/admin/tests/test_mailbox_operations.py
index 6e598bb57..fb2462987 100644
--- a/modoboa/admin/tests/test_mailbox_operations.py
+++ b/modoboa/admin/tests/test_mailbox_operations.py
@@ -1,12 +1,9 @@
-# -*- coding: utf-8 -*-
-
 """Management command tests."""
 
-from __future__ import unicode_literals
-
 import os
 import shutil
 import tempfile
+from unittest import mock
 
 from django.core.management import call_command
 from django.test import override_settings
@@ -15,13 +12,6 @@ from django.urls import reverse
 from modoboa.lib.tests import ModoTestCase
 from .. import factories, models
 
-try:
-    # mock is part of the Python (>= 3.3) standard library
-    from unittest import mock
-except ImportError:
-    # fall back to the mock backport
-    import mock
-
 
 @override_settings(
     DOVECOT_LOOKUP_PATH=["{}/dovecot".format(os.path.dirname(__file__))])
diff --git a/modoboa/admin/tests/test_mapfiles.py b/modoboa/admin/tests/test_mapfiles.py
index 1da822f04..ecc51951d 100644
--- a/modoboa/admin/tests/test_mapfiles.py
+++ b/modoboa/admin/tests/test_mapfiles.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Test map files generation."""
 
-from __future__ import unicode_literals
-
 import os
 
 from django.conf import settings
diff --git a/modoboa/admin/tests/test_mx.py b/modoboa/admin/tests/test_mx.py
index 183ae8382..32e7119f4 100644
--- a/modoboa/admin/tests/test_mx.py
+++ b/modoboa/admin/tests/test_mx.py
@@ -1,8 +1,6 @@
-# -*- coding: utf-8 -*-
-
 """DNSBL related tests."""
 
-from __future__ import unicode_literals
+from unittest import mock
 
 import dns.resolver
 from testfixtures import LogCapture
@@ -18,13 +16,6 @@ from . import utils
 from .. import factories, models
 from ..lib import get_domain_mx_list
 
-try:
-    # mock is part of the Python (>= 3.3) standard library
-    from unittest import mock
-except ImportError:
-    # fall back to the mock backport
-    import mock
-
 
 class MXTestCase(ModoTestCase):
     """TestCase for DNSBL related features."""
diff --git a/modoboa/admin/tests/test_password_schemes.py b/modoboa/admin/tests/test_password_schemes.py
index 61b83b14a..26ecbe41c 100644
--- a/modoboa/admin/tests/test_password_schemes.py
+++ b/modoboa/admin/tests/test_password_schemes.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 from django.urls import reverse
 
 from modoboa.core.models import User
diff --git a/modoboa/admin/tests/test_repair.py b/modoboa/admin/tests/test_repair.py
index 1a45225b0..4a12b6876 100644
--- a/modoboa/admin/tests/test_repair.py
+++ b/modoboa/admin/tests/test_repair.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Repair command tests"""
 
-from __future__ import unicode_literals
-
 from django.core import management
 
 from modoboa.lib.permissions import ObjectAccess, get_object_owner
diff --git a/modoboa/admin/tests/test_user.py b/modoboa/admin/tests/test_user.py
index 3e2238355..312a6c804 100644
--- a/modoboa/admin/tests/test_user.py
+++ b/modoboa/admin/tests/test_user.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """User related tests."""
 
-from __future__ import unicode_literals
-
 from django.urls import reverse
 
 from modoboa.core.models import User
diff --git a/modoboa/admin/tests/utils.py b/modoboa/admin/tests/utils.py
index f0662d5ec..e85f3c41d 100644
--- a/modoboa/admin/tests/utils.py
+++ b/modoboa/admin/tests/utils.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Test utilities."""
 
-from __future__ import unicode_literals
-
 import socket
 
 from dns.name import Name
diff --git a/modoboa/admin/urls.py b/modoboa/admin/urls.py
index bb299ae19..0df5a6705 100644
--- a/modoboa/admin/urls.py
+++ b/modoboa/admin/urls.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Admin urls."""
 
-from __future__ import unicode_literals
-
 from django.conf.urls import url
 
 from . import views
diff --git a/modoboa/admin/urls_api.py b/modoboa/admin/urls_api.py
index 63bad995f..f0c61b428 100644
--- a/modoboa/admin/urls_api.py
+++ b/modoboa/admin/urls_api.py
@@ -1,20 +1,16 @@
-# -*- coding: utf-8 -*-
-
 """Admin API urls."""
 
-from __future__ import unicode_literals
-
 from rest_framework import routers
 
 from . import api
 
 router = routers.SimpleRouter()
-router.register(r"domains", api.DomainViewSet, base_name="domain")
+router.register(r"domains", api.DomainViewSet, basename="domain")
 router.register(
-    r"domainaliases", api.DomainAliasViewSet, base_name="domain_alias")
-router.register(r"accounts", api.AccountViewSet, base_name="account")
-router.register(r"aliases", api.AliasViewSet, base_name="alias")
+    r"domainaliases", api.DomainAliasViewSet, basename="domain_alias")
+router.register(r"accounts", api.AccountViewSet, basename="account")
+router.register(r"aliases", api.AliasViewSet, basename="alias")
 router.register(
-    r"senderaddresses", api.SenderAddressViewSet, base_name="sender_address")
+    r"senderaddresses", api.SenderAddressViewSet, basename="sender_address")
 
 urlpatterns = router.urls
diff --git a/modoboa/admin/views/__init__.py b/modoboa/admin/views/__init__.py
index 501c59517..eb2db5aa2 100644
--- a/modoboa/admin/views/__init__.py
+++ b/modoboa/admin/views/__init__.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Shortcuts."""
 
-from __future__ import unicode_literals
-
 from .alias import AliasDetailView
 from .dns import DNSBLDomainDetailView, MXDomainDetailView
 from .domain import DomainDetailView
diff --git a/modoboa/admin/views/alias.py b/modoboa/admin/views/alias.py
index 9b3dfb1c6..68eeeeeb4 100644
--- a/modoboa/admin/views/alias.py
+++ b/modoboa/admin/views/alias.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Alias related views."""
 
-from __future__ import unicode_literals
-
 from reversion import revisions as reversion
 
 from django.contrib.auth import mixins as auth_mixins
diff --git a/modoboa/admin/views/dns.py b/modoboa/admin/views/dns.py
index e202bb818..42d1738de 100644
--- a/modoboa/admin/views/dns.py
+++ b/modoboa/admin/views/dns.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """DNSBL related views."""
 
-from __future__ import unicode_literals
-
 from django.contrib.auth import mixins as auth_mixins
 from django.utils.translation import ugettext as _
 from django.views import generic
diff --git a/modoboa/admin/views/domain.py b/modoboa/admin/views/domain.py
index b30e29ed6..29550c8fc 100644
--- a/modoboa/admin/views/domain.py
+++ b/modoboa/admin/views/domain.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Domain related views."""
 
-from __future__ import unicode_literals
-
 from functools import reduce
 
 from reversion import revisions as reversion
diff --git a/modoboa/admin/views/export.py b/modoboa/admin/views/export.py
index 281d864d3..5d1764a87 100644
--- a/modoboa/admin/views/export.py
+++ b/modoboa/admin/views/export.py
@@ -1,8 +1,7 @@
-# -*- coding: utf-8 -*-
-
 """Export related views."""
 
-from __future__ import unicode_literals
+import csv
+from io import StringIO
 
 from rfc6266 import build_header
 
@@ -12,17 +11,11 @@ from django.contrib.auth.decorators import (
 from django.http import HttpResponse
 from django.shortcuts import render
 from django.urls import reverse
-from django.utils import six
 from django.utils.translation import ugettext as _
 
 from ..forms import ExportDomainsForm, ExportIdentitiesForm
 from ..lib import get_domains, get_identities
 
-if six.PY2:
-    from backports import csv
-else:
-    import csv
-
 
 def _export(content, filename):
     """Export a csv file's content
@@ -54,7 +47,7 @@ def export_identities(request):
     if request.method == "POST":
         form = ExportIdentitiesForm(request.POST)
         form.is_valid()
-        fp = six.StringIO()
+        fp = StringIO()
         csvwriter = csv.writer(fp, delimiter=form.cleaned_data["sepchar"])
         identities = get_identities(
             request.user, **request.session["identities_filters"])
@@ -82,7 +75,7 @@ def export_domains(request):
     if request.method == "POST":
         form = ExportDomainsForm(request.POST)
         form.is_valid()
-        fp = six.StringIO()
+        fp = StringIO()
         csvwriter = csv.writer(fp, delimiter=form.cleaned_data["sepchar"])
         for dom in get_domains(request.user,
                                **request.session["domains_filters"]):
diff --git a/modoboa/admin/views/identity.py b/modoboa/admin/views/identity.py
index 62ce47d58..1b8b3cf0d 100644
--- a/modoboa/admin/views/identity.py
+++ b/modoboa/admin/views/identity.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Identity related views."""
 
-from __future__ import unicode_literals
-
 from reversion import revisions as reversion
 
 from django.contrib.auth import mixins as auth_mixins
diff --git a/modoboa/admin/views/import_.py b/modoboa/admin/views/import_.py
index 025d9d0e3..b40e4ce28 100644
--- a/modoboa/admin/views/import_.py
+++ b/modoboa/admin/views/import_.py
@@ -1,9 +1,6 @@
-# -*- coding: utf-8 -*-
-
 """Import related views."""
 
-from __future__ import unicode_literals
-
+import csv
 import io
 
 from reversion import revisions as reversion
@@ -14,7 +11,6 @@ from django.contrib.auth.decorators import (
 from django.db import transaction
 from django.shortcuts import render
 from django.urls import reverse
-from django.utils import six
 from django.utils.encoding import smart_text
 from django.utils.translation import ugettext as _
 
@@ -22,11 +18,6 @@ from modoboa.lib.exceptions import Conflict, ModoboaException
 from .. import signals
 from ..forms import ImportDataForm, ImportIdentitiesForm
 
-if six.PY2:
-    from backports import csv
-else:
-    import csv
-
 
 @reversion.create_revision()
 def importdata(request, formclass=ImportDataForm):
diff --git a/modoboa/admin/views/user.py b/modoboa/admin/views/user.py
index cb9e18d12..308cdf268 100644
--- a/modoboa/admin/views/user.py
+++ b/modoboa/admin/views/user.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """SimpleUsers views."""
 
-from __future__ import unicode_literals
-
 from reversion import revisions as reversion
 
 from django.contrib.auth.decorators import login_required
diff --git a/modoboa/core/__init__.py b/modoboa/core/__init__.py
index 4efbc2ba0..0f5234285 100644
--- a/modoboa/core/__init__.py
+++ b/modoboa/core/__init__.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
 """App config for core."""
 
-from __future__ import unicode_literals
-
 default_app_config = "modoboa.core.apps.CoreConfig"
diff --git a/modoboa/core/app_settings.py b/modoboa/core/app_settings.py
index f63f045da..fa254a47d 100644
--- a/modoboa/core/app_settings.py
+++ b/modoboa/core/app_settings.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 from django import forms
 from django.conf import settings
 from django.contrib.auth import password_validation
diff --git a/modoboa/core/apps.py b/modoboa/core/apps.py
index 3e4fa2859..266394abb 100644
--- a/modoboa/core/apps.py
+++ b/modoboa/core/apps.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Core config for admin."""
 
-from __future__ import unicode_literals
-
 from django.apps import AppConfig
 from django.db.models import signals
 from django.utils.translation import ugettext_lazy
diff --git a/modoboa/core/checks/__init__.py b/modoboa/core/checks/__init__.py
index c043b6cf9..9b716b17c 100644
--- a/modoboa/core/checks/__init__.py
+++ b/modoboa/core/checks/__init__.py
@@ -1,6 +1,2 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 # Import these to force registration of checks
 from . import settings_checks  # NOQA:F401
diff --git a/modoboa/core/checks/settings_checks.py b/modoboa/core/checks/settings_checks.py
index ebd09db14..a1efe49d7 100644
--- a/modoboa/core/checks/settings_checks.py
+++ b/modoboa/core/checks/settings_checks.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 from django.conf import settings
 from django.core.checks import Warning, register
 from django.utils.translation import ugettext as _
diff --git a/modoboa/core/commands/__init__.py b/modoboa/core/commands/__init__.py
index 9a07357ce..2f73d5ae6 100644
--- a/modoboa/core/commands/__init__.py
+++ b/modoboa/core/commands/__init__.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import print_function, unicode_literals
-
 import argparse
 import os
 import sys
diff --git a/modoboa/core/commands/deploy.py b/modoboa/core/commands/deploy.py
index 25c81c2e1..ec2b88f66 100644
--- a/modoboa/core/commands/deploy.py
+++ b/modoboa/core/commands/deploy.py
@@ -1,10 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """A shortcut to deploy a fresh modoboa instance."""
 
-from __future__ import print_function, unicode_literals
-
-import codecs
 import getpass
 import os
 import shutil
@@ -18,7 +13,6 @@ import django
 from django.core import management
 from django.template import Context, Template
 from django.utils.encoding import smart_str
-from django.utils.six.moves import input
 
 from modoboa.core.commands import Command
 from modoboa.lib.api_client import ModoAPIClient
@@ -250,7 +244,7 @@ class DeployCommand(Command):
                 "extra_settings": extra_settings
             }
         )
-        with codecs.open("%s/settings.py" % path, "w", "utf-8") as fp:
+        with open("%s/settings.py" % path, "w") as fp:
             fp.write(tpl)
         shutil.copyfile(
             "%s/urls.py.tpl" % self._templates_dir, "%s/urls.py" % path
diff --git a/modoboa/core/commands/help.py b/modoboa/core/commands/help.py
index 931264615..bbfea1916 100644
--- a/modoboa/core/commands/help.py
+++ b/modoboa/core/commands/help.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import print_function, unicode_literals
-
 import sys
 
 from . import Command
diff --git a/modoboa/core/commands/templates/settings.py.tpl b/modoboa/core/commands/templates/settings.py.tpl
index cfd0fc5b7..fd9605784 100644
--- a/modoboa/core/commands/templates/settings.py.tpl
+++ b/modoboa/core/commands/templates/settings.py.tpl
@@ -9,8 +9,6 @@ For the full list of settings and their values, see
 https://docs.djangoproject.com/en/1.11/ref/settings/
 """
 
-from __future__ import unicode_literals
-
 from logging.handlers import SysLogHandler
 import os
 {% if devmode %}
diff --git a/modoboa/core/constants.py b/modoboa/core/constants.py
index b333e61fd..c0db2af39 100644
--- a/modoboa/core/constants.py
+++ b/modoboa/core/constants.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Core application constants."""
 
-from __future__ import unicode_literals
-
 from django.utils.translation import ugettext_lazy
 
 SIMPLEUSERS_ROLE = ("SimpleUsers", ugettext_lazy("Simple user"))
diff --git a/modoboa/core/context_processors.py b/modoboa/core/context_processors.py
index 501b2cdc5..3bd8a3c92 100644
--- a/modoboa/core/context_processors.py
+++ b/modoboa/core/context_processors.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Custom context processors."""
 
-from __future__ import unicode_literals
-
 from functools import reduce
 
 from . import signals
diff --git a/modoboa/core/dev_settings.py b/modoboa/core/dev_settings.py
index c443d5965..5d46afd95 100644
--- a/modoboa/core/dev_settings.py
+++ b/modoboa/core/dev_settings.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 # Development settings
 
-from __future__ import unicode_literals
-
 import os
 
 BOWER_COMPONENTS_ROOT = os.path.join(
diff --git a/modoboa/core/extensions.py b/modoboa/core/extensions.py
index c0287745e..03190dc2f 100644
--- a/modoboa/core/extensions.py
+++ b/modoboa/core/extensions.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Extension management."""
 
-from __future__ import unicode_literals
-
 from django.conf import settings
 from django.conf.urls import include, url
 from django.utils.encoding import smart_str
diff --git a/modoboa/core/factories.py b/modoboa/core/factories.py
index e0ad3315f..c375d09c5 100644
--- a/modoboa/core/factories.py
+++ b/modoboa/core/factories.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Factories for core application."""
 
-from __future__ import unicode_literals
-
 import factory
 
 from django.contrib.auth.models import Group
diff --git a/modoboa/core/forms.py b/modoboa/core/forms.py
index 78e1f3e08..74e0150bc 100644
--- a/modoboa/core/forms.py
+++ b/modoboa/core/forms.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Core forms."""
 
-from __future__ import unicode_literals
-
 from django import forms
 from django.contrib.auth import (
     forms as auth_forms, get_user_model, password_validation
diff --git a/modoboa/core/handlers.py b/modoboa/core/handlers.py
index c964861a7..4f2b063c6 100644
--- a/modoboa/core/handlers.py
+++ b/modoboa/core/handlers.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Modoboa core signal handlers."""
 
-from __future__ import unicode_literals
-
 import logging
 
 from reversion import revisions as reversion
diff --git a/modoboa/core/loggers.py b/modoboa/core/loggers.py
index 9090f5999..35efe0397 100644
--- a/modoboa/core/loggers.py
+++ b/modoboa/core/loggers.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 import logging
 
 
diff --git a/modoboa/core/management/commands/clean_inactive_accounts.py b/modoboa/core/management/commands/clean_inactive_accounts.py
index c67d21358..eb5e58778 100644
--- a/modoboa/core/management/commands/clean_inactive_accounts.py
+++ b/modoboa/core/management/commands/clean_inactive_accounts.py
@@ -1,11 +1,6 @@
-# -*- coding: utf-8 -*-
-
 """Inactive accounts cleanup tool."""
 
-from __future__ import print_function, unicode_literals
-
 from dateutil.relativedelta import relativedelta
-from six.moves import input
 
 from django.core.management.base import BaseCommand
 from django.utils import timezone
diff --git a/modoboa/core/management/commands/cleanlogs.py b/modoboa/core/management/commands/cleanlogs.py
index 723cdf9c0..179aa0262 100644
--- a/modoboa/core/management/commands/cleanlogs.py
+++ b/modoboa/core/management/commands/cleanlogs.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import print_function, unicode_literals
-
 import datetime
 import logging
 
diff --git a/modoboa/core/management/commands/communicate_with_public_api.py b/modoboa/core/management/commands/communicate_with_public_api.py
index 2fe2359c8..eb1bc59d5 100644
--- a/modoboa/core/management/commands/communicate_with_public_api.py
+++ b/modoboa/core/management/commands/communicate_with_public_api.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Management command to communicate with public API."""
 
-from __future__ import unicode_literals
-
 from django.core.management.base import BaseCommand, CommandError
 
 from modoboa.admin import models as admin_models
diff --git a/modoboa/core/management/commands/generate_postfix_maps.py b/modoboa/core/management/commands/generate_postfix_maps.py
index b76fb289b..8f8f11295 100644
--- a/modoboa/core/management/commands/generate_postfix_maps.py
+++ b/modoboa/core/management/commands/generate_postfix_maps.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Management command to generate/update postfix map files."""
 
-from __future__ import print_function, unicode_literals
-
 import copy
 import hashlib
 import os
diff --git a/modoboa/core/management/commands/load_initial_data.py b/modoboa/core/management/commands/load_initial_data.py
index 7811c13e8..446dcd78f 100644
--- a/modoboa/core/management/commands/load_initial_data.py
+++ b/modoboa/core/management/commands/load_initial_data.py
@@ -1,5 +1,3 @@
-# -*- coding: utf-8 -*-
-
 """A management command to load Modoboa initial data:
 
 * Create a default super admin if none exists
@@ -7,8 +5,6 @@
 
 """
 
-from __future__ import unicode_literals
-
 from functools import reduce
 
 from django.contrib.auth.models import Group
diff --git a/modoboa/core/management/commands/set_default_site.py b/modoboa/core/management/commands/set_default_site.py
index 8080420bc..3c77cf2f9 100644
--- a/modoboa/core/management/commands/set_default_site.py
+++ b/modoboa/core/management/commands/set_default_site.py
@@ -1,13 +1,9 @@
-# -*- coding: utf-8 -*-
-
 """
 A simple managemenent command to update the default site.
 
 See `https://docs.djangoproject.com/en/dev/ref/contrib/sites/`_.
 """
 
-from __future__ import unicode_literals
-
 from django.contrib.sites.models import Site
 from django.core.management.base import BaseCommand, CommandError
 
diff --git a/modoboa/core/middleware.py b/modoboa/core/middleware.py
index 65135942f..042bd1a7e 100644
--- a/modoboa/core/middleware.py
+++ b/modoboa/core/middleware.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Core middlewares."""
 
-from __future__ import unicode_literals
-
 from django.utils.deprecation import MiddlewareMixin
 
 from . import models
diff --git a/modoboa/core/migrations/0001_initial.py b/modoboa/core/migrations/0001_initial.py
index 1be0eae38..b8a7ea543 100644
--- a/modoboa/core/migrations/0001_initial.py
+++ b/modoboa/core/migrations/0001_initial.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 import django.utils.timezone
 from django.conf import settings
diff --git a/modoboa/core/migrations/0002_delete_extension.py b/modoboa/core/migrations/0002_delete_extension.py
index 073ef44bb..06ea4b5f1 100644
--- a/modoboa/core/migrations/0002_delete_extension.py
+++ b/modoboa/core/migrations/0002_delete_extension.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/core/migrations/0003_user_master_user.py b/modoboa/core/migrations/0003_user_master_user.py
index 9411bdd5c..b31578867 100644
--- a/modoboa/core/migrations/0003_user_master_user.py
+++ b/modoboa/core/migrations/0003_user_master_user.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/core/migrations/0004_auto_20150728_1228.py b/modoboa/core/migrations/0004_auto_20150728_1228.py
index 202a23da0..ffa20cf95 100644
--- a/modoboa/core/migrations/0004_auto_20150728_1228.py
+++ b/modoboa/core/migrations/0004_auto_20150728_1228.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/core/migrations/0005_user_language.py b/modoboa/core/migrations/0005_user_language.py
index 3f61578ca..849940b58 100644
--- a/modoboa/core/migrations/0005_user_language.py
+++ b/modoboa/core/migrations/0005_user_language.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/core/migrations/0006_auto_20151114_1518.py b/modoboa/core/migrations/0006_auto_20151114_1518.py
index e3c1b88af..40c125697 100644
--- a/modoboa/core/migrations/0006_auto_20151114_1518.py
+++ b/modoboa/core/migrations/0006_auto_20151114_1518.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/core/migrations/0007_auto_20151116_1349.py b/modoboa/core/migrations/0007_auto_20151116_1349.py
index b7d45d14d..e36ddaf1e 100644
--- a/modoboa/core/migrations/0007_auto_20151116_1349.py
+++ b/modoboa/core/migrations/0007_auto_20151116_1349.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.contrib.auth.models
 
diff --git a/modoboa/core/migrations/0008_localconfig.py b/modoboa/core/migrations/0008_localconfig.py
index be8040af8..9dae77efb 100644
--- a/modoboa/core/migrations/0008_localconfig.py
+++ b/modoboa/core/migrations/0008_localconfig.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-06-15 18:12
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.db.models.deletion
 import jsonfield.fields
diff --git a/modoboa/core/migrations/0009_auto_20161026_1003.py b/modoboa/core/migrations/0009_auto_20161026_1003.py
index 51aa18ed8..c65124efe 100644
--- a/modoboa/core/migrations/0009_auto_20161026_1003.py
+++ b/modoboa/core/migrations/0009_auto_20161026_1003.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-10-26 08:03
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/core/migrations/0010_auto_20161026_1011.py b/modoboa/core/migrations/0010_auto_20161026_1011.py
index 64961f261..e681c79b8 100644
--- a/modoboa/core/migrations/0010_auto_20161026_1011.py
+++ b/modoboa/core/migrations/0010_auto_20161026_1011.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-10-26 08:11
-from __future__ import unicode_literals
-
 from django.db import migrations
 import jsonfield.fields
 
diff --git a/modoboa/core/migrations/0011_auto_20161104_2217.py b/modoboa/core/migrations/0011_auto_20161104_2217.py
index 44006a607..f64b2f545 100644
--- a/modoboa/core/migrations/0011_auto_20161104_2217.py
+++ b/modoboa/core/migrations/0011_auto_20161104_2217.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-11-04 21:17
-from __future__ import unicode_literals
-
 from django.db import migrations
 import jsonfield.fields
 
diff --git a/modoboa/core/migrations/0012_auto_20170215_1034.py b/modoboa/core/migrations/0012_auto_20170215_1034.py
index 51e0fd7d3..0adfd9a97 100644
--- a/modoboa/core/migrations/0012_auto_20170215_1034.py
+++ b/modoboa/core/migrations/0012_auto_20170215_1034.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.10.5 on 2017-02-15 09:34
-from __future__ import unicode_literals
-
 from django.db import migrations
 
 
diff --git a/modoboa/core/migrations/0013_auto_20170707_1058.py b/modoboa/core/migrations/0013_auto_20170707_1058.py
index 934a30898..c6ecee2dc 100644
--- a/modoboa/core/migrations/0013_auto_20170707_1058.py
+++ b/modoboa/core/migrations/0013_auto_20170707_1058.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.10.7 on 2017-07-07 08:58
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.utils.timezone
 
diff --git a/modoboa/core/migrations/0014_auto_20171010_1746.py b/modoboa/core/migrations/0014_auto_20171010_1746.py
index 698772236..5d7fd85af 100644
--- a/modoboa/core/migrations/0014_auto_20171010_1746.py
+++ b/modoboa/core/migrations/0014_auto_20171010_1746.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.10.7 on 2017-10-10 15:46
-from __future__ import unicode_literals
-
 from django.db import migrations
 
 
diff --git a/modoboa/core/migrations/0015_auto_20180112_1642.py b/modoboa/core/migrations/0015_auto_20180112_1642.py
index d253aaa52..a3aaea97b 100644
--- a/modoboa/core/migrations/0015_auto_20180112_1642.py
+++ b/modoboa/core/migrations/0015_auto_20180112_1642.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.11.8 on 2018-01-12 15:42
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/core/migrations/0016_auto_20180713_1014.py b/modoboa/core/migrations/0016_auto_20180713_1014.py
index 2315c2a03..9a98017a0 100644
--- a/modoboa/core/migrations/0016_auto_20180713_1014.py
+++ b/modoboa/core/migrations/0016_auto_20180713_1014.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.11.11 on 2018-07-13 08:14
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/core/migrations/0017_auto_20190705_1045.py b/modoboa/core/migrations/0017_auto_20190705_1045.py
index 887a8fc8f..530abdd41 100644
--- a/modoboa/core/migrations/0017_auto_20190705_1045.py
+++ b/modoboa/core/migrations/0017_auto_20190705_1045.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.11.18 on 2019-07-05 08:45
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/core/migrations/__init__.py b/modoboa/core/migrations/__init__.py
index baffc4882..e69de29bb 100644
--- a/modoboa/core/migrations/__init__.py
+++ b/modoboa/core/migrations/__init__.py
@@ -1 +0,0 @@
-from __future__ import unicode_literals
diff --git a/modoboa/core/mocks.py b/modoboa/core/mocks.py
index 53044082b..5637ac21e 100644
--- a/modoboa/core/mocks.py
+++ b/modoboa/core/mocks.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Mocks used for testing."""
 
-from __future__ import unicode_literals
-
 import httmock
 
 # Modoboa API mocks
diff --git a/modoboa/core/models.py b/modoboa/core/models.py
index 18ed79d5f..e7d2743f2 100644
--- a/modoboa/core/models.py
+++ b/modoboa/core/models.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Core models."""
 
-from __future__ import unicode_literals
-
 import re
 from email.header import Header
 
diff --git a/modoboa/core/password_hashers/__init__.py b/modoboa/core/password_hashers/__init__.py
index 2af1b766f..dbb399731 100644
--- a/modoboa/core/password_hashers/__init__.py
+++ b/modoboa/core/password_hashers/__init__.py
@@ -1,11 +1,7 @@
-# -*- coding: utf-8 -*-
-
 """
 Password hashers for Modoboa.
 """
 
-from __future__ import unicode_literals
-
 from django.utils.encoding import smart_text
 
 from modoboa.core.password_hashers.advanced import (  # NOQA:F401
diff --git a/modoboa/core/password_hashers/advanced.py b/modoboa/core/password_hashers/advanced.py
index 1c0a4bd71..75edbf4d8 100644
--- a/modoboa/core/password_hashers/advanced.py
+++ b/modoboa/core/password_hashers/advanced.py
@@ -1,13 +1,9 @@
-# -*- coding: utf-8 -*-
-
 """
 Advanced (ie. stronger) password hashers.
 
 This module relies on `passlib` to provide more secure hashers.
 """
 
-from __future__ import unicode_literals
-
 from passlib.hash import bcrypt, md5_crypt, sha256_crypt, sha512_crypt
 
 try:
diff --git a/modoboa/core/password_hashers/base.py b/modoboa/core/password_hashers/base.py
index 8b354466f..689ffb82a 100644
--- a/modoboa/core/password_hashers/base.py
+++ b/modoboa/core/password_hashers/base.py
@@ -1,13 +1,9 @@
-# -*- coding: utf-8 -*-
-
 """
 Base password hashers.
 
 Contains weak hashers (the original ones) available with Modoboa.
 """
 
-from __future__ import unicode_literals
-
 import base64
 import crypt
 import hashlib
@@ -17,8 +13,6 @@ from random import Random
 from django.utils.crypto import constant_time_compare
 from django.utils.encoding import force_bytes, force_text
 
-from six import with_metaclass
-
 
 class MetaHasher(type):
     """
@@ -36,7 +30,7 @@ class MetaHasher(type):
         return cls.name if not cls._weak else "{} (weak)".format(cls.name)
 
 
-class PasswordHasher(with_metaclass(MetaHasher, object)):
+class PasswordHasher(metaclass=MetaHasher):
     """
     Base class of all hashers.
     """
diff --git a/modoboa/core/password_validation.py b/modoboa/core/password_validation.py
index db3693ba1..3cb944fd7 100644
--- a/modoboa/core/password_validation.py
+++ b/modoboa/core/password_validation.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Custom password validators."""
 
-from __future__ import unicode_literals
-
 from django.core.exceptions import ValidationError
 from django.utils.translation import ugettext as _, ungettext
 
diff --git a/modoboa/core/signals.py b/modoboa/core/signals.py
index 708759fac..409dc2e0b 100644
--- a/modoboa/core/signals.py
+++ b/modoboa/core/signals.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Modoboa core signals."""
 
-from __future__ import unicode_literals
-
 import django.dispatch
 
 account_auto_created = django.dispatch.Signal(providing_args=["user"])
diff --git a/modoboa/core/templatetags/core_tags.py b/modoboa/core/templatetags/core_tags.py
index b0f98ca3c..bc829031e 100644
--- a/modoboa/core/templatetags/core_tags.py
+++ b/modoboa/core/templatetags/core_tags.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Custom tags for Core application."""
 
-from __future__ import unicode_literals
-
 import os
 import re
 from functools import reduce
diff --git a/modoboa/core/tests/stupid_extension_1/modo_extension.py b/modoboa/core/tests/stupid_extension_1/modo_extension.py
index a645634d5..813de845a 100644
--- a/modoboa/core/tests/stupid_extension_1/modo_extension.py
+++ b/modoboa/core/tests/stupid_extension_1/modo_extension.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """A stupid extension used for tests."""
 
-from __future__ import unicode_literals
-
 from modoboa.core import extensions
 
 
diff --git a/modoboa/core/tests/stupid_extension_2/modo_extension.py b/modoboa/core/tests/stupid_extension_2/modo_extension.py
index fd42cb5cb..a8f9052d5 100644
--- a/modoboa/core/tests/stupid_extension_2/modo_extension.py
+++ b/modoboa/core/tests/stupid_extension_2/modo_extension.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """A stupid extension used for tests."""
 
-from __future__ import unicode_literals
-
 from modoboa.core import extensions
 
 
diff --git a/modoboa/core/tests/stupid_extension_2/urls.py b/modoboa/core/tests/stupid_extension_2/urls.py
index 0e3717f91..a7996a92b 100644
--- a/modoboa/core/tests/stupid_extension_2/urls.py
+++ b/modoboa/core/tests/stupid_extension_2/urls.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Custom urls."""
 
-from __future__ import unicode_literals
-
 from django.conf.urls import url
 
 from . import views
diff --git a/modoboa/core/tests/stupid_extension_2/views.py b/modoboa/core/tests/stupid_extension_2/views.py
index c0a372402..4a5f6dd70 100644
--- a/modoboa/core/tests/stupid_extension_2/views.py
+++ b/modoboa/core/tests/stupid_extension_2/views.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 from django import http
 
 
diff --git a/modoboa/core/tests/test_authentication.py b/modoboa/core/tests/test_authentication.py
index 912855f4c..1aec44c21 100644
--- a/modoboa/core/tests/test_authentication.py
+++ b/modoboa/core/tests/test_authentication.py
@@ -1,12 +1,8 @@
-# -*- coding: utf-8 -*-
-
 """Tests for core application."""
 
-from __future__ import unicode_literals
-
 import os
 import smtplib
-from unittest import skipIf, skipUnless
+from unittest import mock, skipIf, skipUnless
 
 from django.core import mail
 from django.test import override_settings
@@ -23,13 +19,6 @@ from modoboa.core.password_hashers import (
 from modoboa.lib.tests import NO_SMTP, ModoTestCase
 from .. import factories, models
 
-try:
-    # mock is part of the Python (>= 3.3) standard library
-    from unittest import mock
-except ImportError:
-    # fall back to the mock backport
-    import mock
-
 
 @override_settings(
     DOVEADM_LOOKUP_PATH=["{}/doveadm".format(os.path.dirname(__file__))])
diff --git a/modoboa/core/tests/test_checks.py b/modoboa/core/tests/test_checks.py
index 124cf3930..06ab8ad58 100644
--- a/modoboa/core/tests/test_checks.py
+++ b/modoboa/core/tests/test_checks.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 from django.test import SimpleTestCase
 from django.test.utils import override_settings
 
diff --git a/modoboa/core/tests/test_core.py b/modoboa/core/tests/test_core.py
index 5d9a5a605..14a04e50a 100644
--- a/modoboa/core/tests/test_core.py
+++ b/modoboa/core/tests/test_core.py
@@ -1,12 +1,9 @@
-# -*- coding: utf-8 -*-
-
 """Tests for core application."""
 
-from __future__ import unicode_literals
+from io import StringIO
 
 import httmock
 from dateutil.relativedelta import relativedelta
-from six import StringIO
 
 from django.core import management
 from django.test import TestCase
diff --git a/modoboa/core/tests/test_extensions.py b/modoboa/core/tests/test_extensions.py
index e9d4e8416..3ef1ec764 100644
--- a/modoboa/core/tests/test_extensions.py
+++ b/modoboa/core/tests/test_extensions.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Extensions management related test cases."""
 
-from __future__ import unicode_literals
-
 import os
 import sys
 from io import StringIO
diff --git a/modoboa/core/tests/test_ldap.py b/modoboa/core/tests/test_ldap.py
index 54c12a31a..1b8cfdf56 100644
--- a/modoboa/core/tests/test_ldap.py
+++ b/modoboa/core/tests/test_ldap.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Tests for core application."""
 
-from __future__ import unicode_literals
-
 from unittest import skipIf
 
 from django.test import override_settings
diff --git a/modoboa/core/tests/test_views.py b/modoboa/core/tests/test_views.py
index 498892c99..838182a81 100644
--- a/modoboa/core/tests/test_views.py
+++ b/modoboa/core/tests/test_views.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Core views test cases."""
 
-from __future__ import unicode_literals
-
 from testfixtures import compare
 
 from django import forms
diff --git a/modoboa/core/urls.py b/modoboa/core/urls.py
index 8b0fd2f95..1d086effd 100644
--- a/modoboa/core/urls.py
+++ b/modoboa/core/urls.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Core urls."""
 
-from __future__ import unicode_literals
-
 from django.conf.urls import url
 
 from . import views
diff --git a/modoboa/core/utils.py b/modoboa/core/utils.py
index 8d992880a..1630f150d 100644
--- a/modoboa/core/utils.py
+++ b/modoboa/core/utils.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Utility functions."""
 
-from __future__ import unicode_literals
-
 from pkg_resources import parse_version
 
 from django.utils.translation import ugettext as _
diff --git a/modoboa/core/views/__init__.py b/modoboa/core/views/__init__.py
index 479f86c7f..c59caeeed 100644
--- a/modoboa/core/views/__init__.py
+++ b/modoboa/core/views/__init__.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Core views."""
 
-from __future__ import unicode_literals
-
 from .admin import (
     check_top_notifications, information, logs, logs_page, parameters,
     viewsettings
diff --git a/modoboa/core/views/admin.py b/modoboa/core/views/admin.py
index d1ec82099..ee4a8b5c9 100644
--- a/modoboa/core/views/admin.py
+++ b/modoboa/core/views/admin.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Views available to super administrators only."""
 
-from __future__ import unicode_literals
-
 from functools import reduce
 
 from django.contrib.auth.decorators import login_required, user_passes_test
diff --git a/modoboa/core/views/auth.py b/modoboa/core/views/auth.py
index 8945f7bf4..cecb7f493 100644
--- a/modoboa/core/views/auth.py
+++ b/modoboa/core/views/auth.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Core authentication views."""
 
-from __future__ import unicode_literals
-
 import logging
 
 from django.contrib.auth import (
diff --git a/modoboa/core/views/base.py b/modoboa/core/views/base.py
index 32ed7651e..33f893f41 100644
--- a/modoboa/core/views/base.py
+++ b/modoboa/core/views/base.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Base core views."""
 
-from __future__ import unicode_literals
-
 from django.contrib.auth import mixins as auth_mixins
 from django.urls import reverse
 from django.utils.http import is_safe_url
diff --git a/modoboa/core/views/dashboard.py b/modoboa/core/views/dashboard.py
index 669bc424d..054c1ad3a 100644
--- a/modoboa/core/views/dashboard.py
+++ b/modoboa/core/views/dashboard.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Core dashboard views."""
 
-from __future__ import unicode_literals
-
 import feedparser
 import requests
 from dateutil import parser
diff --git a/modoboa/core/views/user.py b/modoboa/core/views/user.py
index 22dea631b..11f51a02a 100644
--- a/modoboa/core/views/user.py
+++ b/modoboa/core/views/user.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Simple user views."""
 
-from __future__ import unicode_literals
-
 from django.contrib.auth.decorators import login_required, user_passes_test
 from django.shortcuts import render
 from django.template.loader import render_to_string
diff --git a/modoboa/dnstools/factories.py b/modoboa/dnstools/factories.py
index 4a0b86641..fb8a7710e 100644
--- a/modoboa/dnstools/factories.py
+++ b/modoboa/dnstools/factories.py
@@ -1,7 +1,5 @@
 """App related factories."""
 
-from __future__ import unicode_literals
-
 import factory
 
 from modoboa.admin import factories as admin_factories
diff --git a/modoboa/dnstools/lib.py b/modoboa/dnstools/lib.py
index e66b35283..1fd837ae1 100644
--- a/modoboa/dnstools/lib.py
+++ b/modoboa/dnstools/lib.py
@@ -1,7 +1,5 @@
 """dnstools library."""
 
-from __future__ import unicode_literals
-
 import ipaddress
 
 from django.utils.translation import ugettext as _
diff --git a/modoboa/dnstools/migrations/0001_initial.py b/modoboa/dnstools/migrations/0001_initial.py
index 6fd8e9891..794895dbb 100644
--- a/modoboa/dnstools/migrations/0001_initial.py
+++ b/modoboa/dnstools/migrations/0001_initial.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.11.16 on 2018-11-19 10:07
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.db.models.deletion
 import django.utils.timezone
diff --git a/modoboa/dnstools/models.py b/modoboa/dnstools/models.py
index 20e0a8d89..a2bd43a37 100644
--- a/modoboa/dnstools/models.py
+++ b/modoboa/dnstools/models.py
@@ -1,7 +1,5 @@
 """App related models."""
 
-from __future__ import unicode_literals
-
 import datetime
 
 from django.db import models
diff --git a/modoboa/ldapsync/lib.py b/modoboa/ldapsync/lib.py
index 89b371680..fd8a345c1 100644
--- a/modoboa/ldapsync/lib.py
+++ b/modoboa/ldapsync/lib.py
@@ -1,7 +1,5 @@
 """LDAP related functions."""
 
-from __future__ import unicode_literals
-
 import ldap
 import ldap.modlist as modlist
 
diff --git a/modoboa/ldapsync/tests.py b/modoboa/ldapsync/tests.py
index 448d28ae9..e5a633307 100644
--- a/modoboa/ldapsync/tests.py
+++ b/modoboa/ldapsync/tests.py
@@ -1,10 +1,7 @@
 """LDAP sync. related tests."""
 
-from __future__ import unicode_literals
-
 from unittest import skipIf
 
-from django.utils import six
 from django.utils.encoding import force_bytes, force_str
 
 from modoboa.core import factories as core_factories
@@ -38,8 +35,7 @@ class LDAPSyncTestCase(ModoTestCase):
 
     def reset_ldap_directory(self):
         try:
-            tmp_dn = force_bytes(self.dn) if six.PY2 else self.dn
-            self.conn.delete_s(tmp_dn)
+            self.conn.delete_s(self.dn)
         except ldap.NO_SUCH_OBJECT:
             pass
 
diff --git a/modoboa/lib/api_client.py b/modoboa/lib/api_client.py
index 70cf45d87..504d0cf07 100644
--- a/modoboa/lib/api_client.py
+++ b/modoboa/lib/api_client.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """A client for Modoboa's public API."""
 
-from __future__ import unicode_literals
-
 import os
 
 import pkg_resources
diff --git a/modoboa/lib/authbackends.py b/modoboa/lib/authbackends.py
index 9f8644726..87bfd676d 100644
--- a/modoboa/lib/authbackends.py
+++ b/modoboa/lib/authbackends.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Custom authentication backends."""
 
-from __future__ import unicode_literals
-
 import smtplib
 
 from django.conf import settings
diff --git a/modoboa/lib/connections.py b/modoboa/lib/connections.py
index 5a194f674..fcc1b51eb 100644
--- a/modoboa/lib/connections.py
+++ b/modoboa/lib/connections.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 from modoboa.lib.cryptutils import decrypt
 
 
diff --git a/modoboa/lib/cryptutils.py b/modoboa/lib/cryptutils.py
index 41815a38f..8ba6b36b6 100644
--- a/modoboa/lib/cryptutils.py
+++ b/modoboa/lib/cryptutils.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Crypto related utilities."""
 
-from __future__ import unicode_literals
-
 import base64
 
 from cryptography.fernet import Fernet
diff --git a/modoboa/lib/db_utils.py b/modoboa/lib/db_utils.py
index 3336ed1ac..569bc8e9f 100644
--- a/modoboa/lib/db_utils.py
+++ b/modoboa/lib/db_utils.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 from django.conf import settings
 from django.db import connection
 from django.utils.translation import ugettext as _
diff --git a/modoboa/lib/email_utils.py b/modoboa/lib/email_utils.py
index 3eb25b9f0..8e0d3c544 100644
--- a/modoboa/lib/email_utils.py
+++ b/modoboa/lib/email_utils.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 import email
 import re
 import smtplib
@@ -16,7 +12,6 @@ from lxml.html import defs
 from lxml.html.clean import Cleaner
 
 from django.template.loader import render_to_string
-from django.utils import six
 from django.utils.encoding import smart_str, smart_text
 from django.utils.html import conditional_escape, escape
 from django.utils.translation import ugettext as _
@@ -134,7 +129,7 @@ class Email(object):
                     continue
                 if encoding:
                     value = smart_text(value, encoding=encoding)
-                elif isinstance(value, six.binary_type):
+                elif isinstance(value, bytes):
                     # SMTPUTF8 fallback (most of the time)
                     # Address contains non ASCII chars but is not RFC2047
                     # encoded...
@@ -142,12 +137,9 @@ class Email(object):
                     try:
                         value = value.decode(encoding["encoding"], "replace")
                     except (TypeError, UnicodeDecodeError) as exc:
-                        six.raise_from(
-                            InternalError(
-                                _("unable to determine encoding of string")
-                            ),
-                            exc
-                        )
+                        raise InternalError(
+                            _("unable to determine encoding of string")
+                        ) from exc
                 decoded_values.append(value)
             return "".join(decoded_values)
         return ""
@@ -293,8 +285,8 @@ class Email(object):
 
 def split_address(address):
     """Split an e-mail address into local part and domain."""
-    assert isinstance(address, six.text_type),\
-        "address should be of type %s" % six.text_type.__name__
+    assert isinstance(address, str),\
+        "address should be of type str"
     if "@" not in address:
         local_part = address
         domain = None
@@ -305,10 +297,10 @@ def split_address(address):
 
 def split_local_part(local_part, delimiter=None):
     """Split a local part into local part and extension."""
-    assert isinstance(local_part, six.text_type),\
-        "local_part should be of type %s" % six.text_type.__name__
-    assert isinstance(delimiter, six.text_type) or delimiter is None,\
-        "delimiter should be of type %s" % six.text_type.__name__
+    assert isinstance(local_part, str),\
+        "local_part should be of type str"
+    assert isinstance(delimiter, str) or delimiter is None,\
+        "delimiter should be of type str"
     extension = None
     if local_part.lower() in ["mailer-daemon", "double-bounce"]:
         # never split these special addresses
@@ -350,8 +342,8 @@ def split_mailbox(mailbox, return_extension=False):
 
 def decode(value_bytes, encoding, append_to_error=""):
     """Try to decode the given string."""
-    assert isinstance(value_bytes, six.binary_type),\
-        "value_bytes should be of type %s" % six.binary_type.__name__
+    assert isinstance(value_bytes, bytes),\
+        "value_bytes should be of type bytes"
     if len(value_bytes) == 0:
         # short circuit for empty strings
         return ""
@@ -364,13 +356,10 @@ def decode(value_bytes, encoding, append_to_error=""):
                 encoding["encoding"], "replace"
             )
         except (TypeError, UnicodeDecodeError) as exc:
-            six.raise_from(
-                InternalError(
-                    _("unable to determine encoding of string") +
-                    append_to_error
-                ),
-                exc
-            )
+            raise InternalError(
+                _("unable to determine encoding of string") +
+                append_to_error
+            ) from exc
     return value
 
 
@@ -382,7 +371,7 @@ def prepare_addresses(addresses, usage="header"):
     :return: a string or a list depending on usage value
     """
     result = []
-    if isinstance(addresses, six.text_type):
+    if isinstance(addresses, str):
         addresses = [addresses]
     for name, address in getaddresses(addresses):
         if not address:
diff --git a/modoboa/lib/exceptions.py b/modoboa/lib/exceptions.py
index 9a672e8ca..2e740597d 100644
--- a/modoboa/lib/exceptions.py
+++ b/modoboa/lib/exceptions.py
@@ -1,13 +1,9 @@
-# -*- coding: utf-8 -*-
-
 """
 :mod:`exceptions` --- Custom Modoboa exceptions
 -----------------------------------------------
 
 """
 
-from __future__ import unicode_literals
-
 from django.utils.translation import ugettext as _
 
 
diff --git a/modoboa/lib/fields.py b/modoboa/lib/fields.py
index 52f53cd72..c5e81ff11 100644
--- a/modoboa/lib/fields.py
+++ b/modoboa/lib/fields.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Custom form fields."""
 
-from __future__ import unicode_literals
-
 from django import forms
 from django.utils.translation import ugettext_lazy
 
diff --git a/modoboa/lib/form_utils.py b/modoboa/lib/form_utils.py
index 937e0e8d9..c98036884 100644
--- a/modoboa/lib/form_utils.py
+++ b/modoboa/lib/form_utils.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Form management utilities."""
 
-from __future__ import unicode_literals
-
 import abc
 import re
 from collections import OrderedDict
diff --git a/modoboa/lib/imap_utf7.py b/modoboa/lib/imap_utf7.py
index 34efc3778..95caa987b 100644
--- a/modoboa/lib/imap_utf7.py
+++ b/modoboa/lib/imap_utf7.py
@@ -51,8 +51,6 @@ Found here:
 http://svn.plone.org/svn/collective/mxmImapClient/trunk/imapUTF7.py
 
 """
-from __future__ import print_function, unicode_literals
-
 import codecs
 
 # encoding
diff --git a/modoboa/lib/ldap_utils.py b/modoboa/lib/ldap_utils.py
index c7ec9235d..c981c25ab 100644
--- a/modoboa/lib/ldap_utils.py
+++ b/modoboa/lib/ldap_utils.py
@@ -1,5 +1,3 @@
-# -*- coding: utf-8 -*-
-
 """
 A collection of LDAP based classes/functions.
 
@@ -33,12 +31,9 @@ Extracted from `this blog
 
 """
 
-from __future__ import unicode_literals
-
 import ldap
 
 from django.conf import settings
-from django.utils import six
 from django.utils.encoding import force_bytes, force_str
 from django.utils.translation import ugettext as _
 
@@ -70,7 +65,7 @@ class LDAPAuthBackend(object):
 
     def _get_conn(self, dn, password):
         """Get a connection from the server."""
-        conn = ldap.initialize(self.server_uri, bytes_mode=six.PY2)
+        conn = ldap.initialize(self.server_uri)
         conn.set_option(ldap.OPT_X_TLS_DEMAND, True)
         conn.set_option(ldap.OPT_DEBUG_LEVEL, 255)
         conn.simple_bind_s(
diff --git a/modoboa/lib/listing.py b/modoboa/lib/listing.py
index 8237719fe..3e5f432d1 100644
--- a/modoboa/lib/listing.py
+++ b/modoboa/lib/listing.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 from django.core.paginator import EmptyPage, PageNotAnInteger, Paginator
 
 from modoboa.parameters import tools as param_tools
diff --git a/modoboa/lib/middleware.py b/modoboa/lib/middleware.py
index 2273e6b1e..5262af691 100644
--- a/modoboa/lib/middleware.py
+++ b/modoboa/lib/middleware.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Custom middlewares."""
 
-from __future__ import unicode_literals
-
 from django.http import HttpResponseRedirect
 from django.utils.deprecation import MiddlewareMixin
 from django.utils.encoding import smart_text
diff --git a/modoboa/lib/migrations/0001_initial.py b/modoboa/lib/migrations/0001_initial.py
index 6f5cd6f93..7ffa0a642 100644
--- a/modoboa/lib/migrations/0001_initial.py
+++ b/modoboa/lib/migrations/0001_initial.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 from django.conf import settings
 
diff --git a/modoboa/lib/migrations/0002_rename_parameters.py b/modoboa/lib/migrations/0002_rename_parameters.py
index da484142b..90dcb9647 100644
--- a/modoboa/lib/migrations/0002_rename_parameters.py
+++ b/modoboa/lib/migrations/0002_rename_parameters.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 APPLICATIONS = [
diff --git a/modoboa/lib/migrations/0003_rename_parameters.py b/modoboa/lib/migrations/0003_rename_parameters.py
index 642e5a5a8..4dd10cdff 100644
--- a/modoboa/lib/migrations/0003_rename_parameters.py
+++ b/modoboa/lib/migrations/0003_rename_parameters.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 APPS = (
diff --git a/modoboa/lib/migrations/0004_auto_20151114_1409.py b/modoboa/lib/migrations/0004_auto_20151114_1409.py
index e66d38167..5c62719ba 100644
--- a/modoboa/lib/migrations/0004_auto_20151114_1409.py
+++ b/modoboa/lib/migrations/0004_auto_20151114_1409.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/lib/migrations/0005_auto_20160416_1449.py b/modoboa/lib/migrations/0005_auto_20160416_1449.py
index 6c594dec3..250bc6be7 100644
--- a/modoboa/lib/migrations/0005_auto_20160416_1449.py
+++ b/modoboa/lib/migrations/0005_auto_20160416_1449.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import migrations
 
 
diff --git a/modoboa/lib/migrations/0006_auto_20161104_2206.py b/modoboa/lib/migrations/0006_auto_20161104_2206.py
index 105af9718..10bf96658 100644
--- a/modoboa/lib/migrations/0006_auto_20161104_2206.py
+++ b/modoboa/lib/migrations/0006_auto_20161104_2206.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-11-04 21:06
-from __future__ import unicode_literals
-
 from django.db import migrations
 
 
diff --git a/modoboa/lib/migrations/__init__.py b/modoboa/lib/migrations/__init__.py
index baffc4882..e69de29bb 100644
--- a/modoboa/lib/migrations/__init__.py
+++ b/modoboa/lib/migrations/__init__.py
@@ -1 +0,0 @@
-from __future__ import unicode_literals
diff --git a/modoboa/lib/paginator.py b/modoboa/lib/paginator.py
index 9006ded56..3dfc8f54a 100644
--- a/modoboa/lib/paginator.py
+++ b/modoboa/lib/paginator.py
@@ -1,12 +1,7 @@
-# -*- coding: utf-8 -*-
-
 """
 Custom pagination tools.
 """
 
-from __future__ import unicode_literals
-
-
 class Page(object):
 
     """Class to represent a page."""
diff --git a/modoboa/lib/permissions.py b/modoboa/lib/permissions.py
index b1705bd77..5f7d27af6 100644
--- a/modoboa/lib/permissions.py
+++ b/modoboa/lib/permissions.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Object level permissions."""
 
-from __future__ import unicode_literals
-
 from django.contrib.auth.models import Group, Permission
 from django.contrib.contenttypes.models import ContentType
 
diff --git a/modoboa/lib/signals.py b/modoboa/lib/signals.py
index 46c4795b1..2a114e8c3 100644
--- a/modoboa/lib/signals.py
+++ b/modoboa/lib/signals.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Custom signals."""
 
-from __future__ import unicode_literals
-
 from threading import local
 
 _local_store = local()
diff --git a/modoboa/lib/singleton.py b/modoboa/lib/singleton.py
index 2033d7c6e..977a8590b 100644
--- a/modoboa/lib/singleton.py
+++ b/modoboa/lib/singleton.py
@@ -1,8 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
-
 # works in Python 2 & 3
 class _Singleton(type):
     _instances = {}
diff --git a/modoboa/lib/sysutils.py b/modoboa/lib/sysutils.py
index eb0b8c92f..05e84c41f 100644
--- a/modoboa/lib/sysutils.py
+++ b/modoboa/lib/sysutils.py
@@ -1,12 +1,8 @@
-# -*- coding: utf-8 -*-
-
 """
 This module extra functions/shortcuts to communicate with the system
 (executing commands, etc.)
 """
 
-from __future__ import unicode_literals
-
 import inspect
 import os
 import re
diff --git a/modoboa/lib/templatetags/form_tags.py b/modoboa/lib/templatetags/form_tags.py
index 796fce0be..b7d7e3e4b 100644
--- a/modoboa/lib/templatetags/form_tags.py
+++ b/modoboa/lib/templatetags/form_tags.py
@@ -1,11 +1,7 @@
-# -*- coding: utf-8 -*-
-
 """
 Form rendering tags.
 """
 
-from __future__ import unicode_literals
-
 from django import forms, template
 from django.template.loader import render_to_string
 from django.utils.encoding import smart_text
diff --git a/modoboa/lib/templatetags/lib_tags.py b/modoboa/lib/templatetags/lib_tags.py
index 41a086d31..22cf15146 100644
--- a/modoboa/lib/templatetags/lib_tags.py
+++ b/modoboa/lib/templatetags/lib_tags.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Custom template tags."""
 
-from __future__ import unicode_literals
-
 from datetime import datetime
 
 from django import template
diff --git a/modoboa/lib/test_utils.py b/modoboa/lib/test_utils.py
index 51b4be356..e4bb1e4d9 100644
--- a/modoboa/lib/test_utils.py
+++ b/modoboa/lib/test_utils.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Tools for top level testing (ie. when ran by Travis)."""
 
-from __future__ import unicode_literals
-
 import os
 import shutil
 import tempfile
diff --git a/modoboa/lib/tests/__init__.py b/modoboa/lib/tests/__init__.py
index 7eb668515..0441301d5 100644
--- a/modoboa/lib/tests/__init__.py
+++ b/modoboa/lib/tests/__init__.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Testing utilities."""
 
-from __future__ import unicode_literals
-
 import socket
 
 from django.core import management
diff --git a/modoboa/lib/tests/test_cryptutils.py b/modoboa/lib/tests/test_cryptutils.py
index 4c3f852d9..e50c3adac 100644
--- a/modoboa/lib/tests/test_cryptutils.py
+++ b/modoboa/lib/tests/test_cryptutils.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Tests for crypto utility functions."""
 
-from __future__ import unicode_literals
-
 from django.test import SimpleTestCase
 from django.test.utils import override_settings
 
diff --git a/modoboa/lib/tests/test_email_utils.py b/modoboa/lib/tests/test_email_utils.py
index 6b2c8bbc4..b64007d3b 100644
--- a/modoboa/lib/tests/test_email_utils.py
+++ b/modoboa/lib/tests/test_email_utils.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Tests for email_utils."""
 
-from __future__ import unicode_literals
-
 import os
 
 from django.test import SimpleTestCase
diff --git a/modoboa/lib/tests/test_u2u_decode.py b/modoboa/lib/tests/test_u2u_decode.py
index 9c64cae46..464aa4a24 100644
--- a/modoboa/lib/tests/test_u2u_decode.py
+++ b/modoboa/lib/tests/test_u2u_decode.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Tests for u2u_decode."""
 
-from __future__ import unicode_literals
-
 from django.test import TestCase
 
 from .. import u2u_decode
diff --git a/modoboa/lib/u2u_decode.py b/modoboa/lib/u2u_decode.py
index 5d9367557..34a89e917 100644
--- a/modoboa/lib/u2u_decode.py
+++ b/modoboa/lib/u2u_decode.py
@@ -1,5 +1,3 @@
-# -*- coding: utf-8 -*-
-
 """
 Unstructured rfc2047 header to unicode.
 
@@ -7,8 +5,6 @@ A stupid (and not accurate) answer to https://bugs.python.org/issue1079.
 
 """
 
-from __future__ import unicode_literals
-
 import re
 from email.header import decode_header, make_header
 from email.utils import parseaddr
diff --git a/modoboa/lib/validators.py b/modoboa/lib/validators.py
index 80bd95ca2..fd7e4b91f 100644
--- a/modoboa/lib/validators.py
+++ b/modoboa/lib/validators.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Field validators."""
 
-from __future__ import unicode_literals
-
 import re
 
 from django.core.exceptions import ValidationError
diff --git a/modoboa/lib/web_utils.py b/modoboa/lib/web_utils.py
index de54f63df..443da7f81 100644
--- a/modoboa/lib/web_utils.py
+++ b/modoboa/lib/web_utils.py
@@ -1,11 +1,7 @@
-# -*- coding: utf-8 -*-
-
 """
 This module contains extra functions/shortcuts used to render HTML.
 """
 
-from __future__ import unicode_literals
-
 import json
 import re
 import sys
diff --git a/modoboa/limits/__init__.py b/modoboa/limits/__init__.py
index 01758a791..1816137f6 100644
--- a/modoboa/limits/__init__.py
+++ b/modoboa/limits/__init__.py
@@ -1,5 +1 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 default_app_config = "modoboa.limits.apps.LimitsConfig"
diff --git a/modoboa/limits/app_settings.py b/modoboa/limits/app_settings.py
index 070a38f23..cf77296b3 100644
--- a/modoboa/limits/app_settings.py
+++ b/modoboa/limits/app_settings.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Custom settings."""
 
-from __future__ import unicode_literals
-
 from django import forms
 from django.utils.translation import ugettext_lazy as _
 
diff --git a/modoboa/limits/apps.py b/modoboa/limits/apps.py
index 7f066caf0..f4de69920 100644
--- a/modoboa/limits/apps.py
+++ b/modoboa/limits/apps.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """App config for limits."""
 
-from __future__ import unicode_literals
-
 from django.apps import AppConfig
 from django.utils.translation import ugettext as _
 
diff --git a/modoboa/limits/constants.py b/modoboa/limits/constants.py
index 570d961aa..c916b2b93 100644
--- a/modoboa/limits/constants.py
+++ b/modoboa/limits/constants.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Modoboa limits constants."""
 
-from __future__ import unicode_literals
-
 import collections
 
 from django.utils.translation import ugettext_lazy as _
diff --git a/modoboa/limits/forms.py b/modoboa/limits/forms.py
index 7b91c377d..ac6842505 100644
--- a/modoboa/limits/forms.py
+++ b/modoboa/limits/forms.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Custom forms."""
 
-from __future__ import unicode_literals
-
 from django import forms
 from django.utils.translation import ugettext as _
 
diff --git a/modoboa/limits/handlers.py b/modoboa/limits/handlers.py
index 57309b405..a73bb8d19 100644
--- a/modoboa/limits/handlers.py
+++ b/modoboa/limits/handlers.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Django signal handlers for limits."""
 
-from __future__ import unicode_literals
-
 from django.contrib.contenttypes.models import ContentType
 from django.db.models import signals
 from django.dispatch import receiver
diff --git a/modoboa/limits/lib.py b/modoboa/limits/lib.py
index 68dcb734a..7da7b97e8 100644
--- a/modoboa/limits/lib.py
+++ b/modoboa/limits/lib.py
@@ -1,13 +1,9 @@
-# -*- coding: utf-8 -*-
-
 """
 :mod:`lib` --- public functions
 -------------------------------
 
 """
 
-from __future__ import unicode_literals
-
 from django.utils.translation import ugettext as _
 
 from modoboa.lib.exceptions import ModoboaException
diff --git a/modoboa/limits/migrations/0001_initial.py b/modoboa/limits/migrations/0001_initial.py
index 2c1d96230..c40f69b92 100644
--- a/modoboa/limits/migrations/0001_initial.py
+++ b/modoboa/limits/migrations/0001_initial.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 from django.conf import settings
 
diff --git a/modoboa/limits/migrations/0002_auto_20151114_1518.py b/modoboa/limits/migrations/0002_auto_20151114_1518.py
index a6ed7714f..7982519e0 100644
--- a/modoboa/limits/migrations/0002_auto_20151114_1518.py
+++ b/modoboa/limits/migrations/0002_auto_20151114_1518.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/limits/migrations/0003_auto_20160413_1046.py b/modoboa/limits/migrations/0003_auto_20160413_1046.py
index 625a90568..941802bb6 100644
--- a/modoboa/limits/migrations/0003_auto_20160413_1046.py
+++ b/modoboa/limits/migrations/0003_auto_20160413_1046.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 from django.conf import settings
 
diff --git a/modoboa/limits/migrations/0004_auto_20160413_1312.py b/modoboa/limits/migrations/0004_auto_20160413_1312.py
index fe085dd35..1ec5502f7 100644
--- a/modoboa/limits/migrations/0004_auto_20160413_1312.py
+++ b/modoboa/limits/migrations/0004_auto_20160413_1312.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/limits/migrations/0005_auto_20160415_1654.py b/modoboa/limits/migrations/0005_auto_20160415_1654.py
index 9b05b9f08..63d8c760d 100644
--- a/modoboa/limits/migrations/0005_auto_20160415_1654.py
+++ b/modoboa/limits/migrations/0005_auto_20160415_1654.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import modoboa.limits.models
 
diff --git a/modoboa/limits/migrations/0006_auto_20170216_1112.py b/modoboa/limits/migrations/0006_auto_20170216_1112.py
index d195d54b1..a2ac72b32 100644
--- a/modoboa/limits/migrations/0006_auto_20170216_1112.py
+++ b/modoboa/limits/migrations/0006_auto_20170216_1112.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.10.5 on 2017-02-16 10:12
-from __future__ import unicode_literals
-
 from django.db import migrations
 
 
diff --git a/modoboa/limits/migrations/__init__.py b/modoboa/limits/migrations/__init__.py
index baffc4882..e69de29bb 100644
--- a/modoboa/limits/migrations/__init__.py
+++ b/modoboa/limits/migrations/__init__.py
@@ -1 +0,0 @@
-from __future__ import unicode_literals
diff --git a/modoboa/limits/models.py b/modoboa/limits/models.py
index ce62d9bfc..9e9f58f70 100644
--- a/modoboa/limits/models.py
+++ b/modoboa/limits/models.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Models for the limits extensions."""
 
-from __future__ import unicode_literals
-
 from django.conf import settings
 from django.db import models
 from django.utils.encoding import python_2_unicode_compatible
diff --git a/modoboa/limits/serializers.py b/modoboa/limits/serializers.py
index 9fa0cbd00..ed9c85e73 100644
--- a/modoboa/limits/serializers.py
+++ b/modoboa/limits/serializers.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Limits serializers."""
 
-from __future__ import unicode_literals
-
 from rest_framework import serializers
 
 from . import lib
diff --git a/modoboa/limits/tests/test_api.py b/modoboa/limits/tests/test_api.py
index 890c05556..63aa057f2 100644
--- a/modoboa/limits/tests/test_api.py
+++ b/modoboa/limits/tests/test_api.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Test cases for the limits extension."""
 
-from __future__ import unicode_literals
-
 from testfixtures import compare
 
 from django.urls import reverse
diff --git a/modoboa/limits/tests/test_domain_limits.py b/modoboa/limits/tests/test_domain_limits.py
index 9442cda99..545105f0b 100644
--- a/modoboa/limits/tests/test_domain_limits.py
+++ b/modoboa/limits/tests/test_domain_limits.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Test cases for the limits extension."""
 
-from __future__ import unicode_literals
-
 from django.urls import reverse
 
 from modoboa.admin import factories as admin_factories
diff --git a/modoboa/limits/tests/test_import.py b/modoboa/limits/tests/test_import.py
index 109021f45..e59002b01 100644
--- a/modoboa/limits/tests/test_import.py
+++ b/modoboa/limits/tests/test_import.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 from django.core.files.base import ContentFile
 from django.urls import reverse
 
diff --git a/modoboa/limits/tests/test_user_limits.py b/modoboa/limits/tests/test_user_limits.py
index 41bb40706..4e514ffc7 100644
--- a/modoboa/limits/tests/test_user_limits.py
+++ b/modoboa/limits/tests/test_user_limits.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Test cases for the limits extension."""
 
-from __future__ import unicode_literals
-
 from django.urls import reverse
 
 from modoboa.admin.factories import populate_database
diff --git a/modoboa/limits/urls_api.py b/modoboa/limits/urls_api.py
index 8295e069f..621a83286 100644
--- a/modoboa/limits/urls_api.py
+++ b/modoboa/limits/urls_api.py
@@ -1,15 +1,11 @@
-# -*- coding: utf-8 -*-
-
 """Limits API urls."""
 
-from __future__ import unicode_literals
-
 from rest_framework import routers
 
 from . import viewsets
 
 router = routers.SimpleRouter()
 router.register(
-    r"resources", viewsets.ResourcesViewSet, base_name="resources")
+    r"resources", viewsets.ResourcesViewSet, basename="resources")
 
 urlpatterns = router.urls
diff --git a/modoboa/limits/utils.py b/modoboa/limits/utils.py
index ebbb11972..89fe797ff 100644
--- a/modoboa/limits/utils.py
+++ b/modoboa/limits/utils.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Modoboa limits utilities."""
 
-from __future__ import unicode_literals
-
 from . import constants
 
 
diff --git a/modoboa/limits/viewsets.py b/modoboa/limits/viewsets.py
index 7cb8b3e55..6e6c6ad3f 100644
--- a/modoboa/limits/viewsets.py
+++ b/modoboa/limits/viewsets.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Limits API."""
 
-from __future__ import unicode_literals
-
 from django.contrib.contenttypes.models import ContentType
 
 from rest_framework import mixins, viewsets
diff --git a/modoboa/parameters/apps.py b/modoboa/parameters/apps.py
index f60d64f47..b3ed16382 100644
--- a/modoboa/parameters/apps.py
+++ b/modoboa/parameters/apps.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 from django.apps import AppConfig
 
 
diff --git a/modoboa/parameters/forms.py b/modoboa/parameters/forms.py
index 19243c7b0..20e16aa85 100644
--- a/modoboa/parameters/forms.py
+++ b/modoboa/parameters/forms.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Parameters forms."""
 
-from __future__ import unicode_literals
-
 from django import forms
 
 from modoboa.lib import db_utils, form_utils
diff --git a/modoboa/parameters/tools.py b/modoboa/parameters/tools.py
index 5187ec0a5..9c792ffc6 100644
--- a/modoboa/parameters/tools.py
+++ b/modoboa/parameters/tools.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Parameters management."""
 
-from __future__ import unicode_literals
-
 import copy
 
 from modoboa.lib import exceptions, form_utils, signals
diff --git a/modoboa/relaydomains/__init__.py b/modoboa/relaydomains/__init__.py
index 05dc26897..0b2987e99 100644
--- a/modoboa/relaydomains/__init__.py
+++ b/modoboa/relaydomains/__init__.py
@@ -1,5 +1 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 default_app_config = "modoboa.relaydomains.apps.RelayDomainsConfig"
diff --git a/modoboa/relaydomains/apps.py b/modoboa/relaydomains/apps.py
index cfdb726b3..49ffe5fc8 100644
--- a/modoboa/relaydomains/apps.py
+++ b/modoboa/relaydomains/apps.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """AppConfig for relaydomains."""
 
-from __future__ import unicode_literals
-
 from django.apps import AppConfig
 
 
diff --git a/modoboa/relaydomains/forms.py b/modoboa/relaydomains/forms.py
index f9b40e6d6..9b52086b4 100644
--- a/modoboa/relaydomains/forms.py
+++ b/modoboa/relaydomains/forms.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Postfix relay domains extension forms."""
 
-from __future__ import unicode_literals
-
 from django.db.models.signals import pre_save, post_save
 
 from modoboa.lib.form_utils import WizardStep
diff --git a/modoboa/relaydomains/handlers.py b/modoboa/relaydomains/handlers.py
index b06effa28..14102bdd4 100644
--- a/modoboa/relaydomains/handlers.py
+++ b/modoboa/relaydomains/handlers.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Django signal handlers for relaydomains."""
 
-from __future__ import unicode_literals
-
 from django.db.models import signals
 from django.dispatch import receiver
 from django.utils.translation import ugettext as _
diff --git a/modoboa/relaydomains/lib.py b/modoboa/relaydomains/lib.py
index bcebef70b..41d28eb40 100644
--- a/modoboa/relaydomains/lib.py
+++ b/modoboa/relaydomains/lib.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Internal library."""
 
-from __future__ import unicode_literals
-
 from django.utils.translation import ugettext as _
 
 from modoboa.admin import models as admin_models
diff --git a/modoboa/relaydomains/migrations/0001_initial.py b/modoboa/relaydomains/migrations/0001_initial.py
index 84cf66c6a..cd708a483 100644
--- a/modoboa/relaydomains/migrations/0001_initial.py
+++ b/modoboa/relaydomains/migrations/0001_initial.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/relaydomains/migrations/0002_migrate_from_modoboa_admin_relaydomains.py b/modoboa/relaydomains/migrations/0002_migrate_from_modoboa_admin_relaydomains.py
index e100533fc..5fd89c6a3 100644
--- a/modoboa/relaydomains/migrations/0002_migrate_from_modoboa_admin_relaydomains.py
+++ b/modoboa/relaydomains/migrations/0002_migrate_from_modoboa_admin_relaydomains.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import models, migrations
 
 
diff --git a/modoboa/relaydomains/migrations/0003_auto_20170116_1508.py b/modoboa/relaydomains/migrations/0003_auto_20170116_1508.py
index 19c94ce5b..bec153bd8 100644
--- a/modoboa/relaydomains/migrations/0003_auto_20170116_1508.py
+++ b/modoboa/relaydomains/migrations/0003_auto_20170116_1508.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.9.12 on 2017-01-16 14:08
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/relaydomains/migrations/0004_auto_20161105_1424.py b/modoboa/relaydomains/migrations/0004_auto_20161105_1424.py
index 7c0320a81..e426a035d 100644
--- a/modoboa/relaydomains/migrations/0004_auto_20161105_1424.py
+++ b/modoboa/relaydomains/migrations/0004_auto_20161105_1424.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-11-05 13:24
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.utils.timezone
 
diff --git a/modoboa/relaydomains/migrations/0005_auto_20161105_1426.py b/modoboa/relaydomains/migrations/0005_auto_20161105_1426.py
index a056781d5..e51a96764 100644
--- a/modoboa/relaydomains/migrations/0005_auto_20161105_1426.py
+++ b/modoboa/relaydomains/migrations/0005_auto_20161105_1426.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.9.5 on 2016-11-05 13:26
-from __future__ import unicode_literals
-
 from django.db import migrations
 
 
diff --git a/modoboa/relaydomains/migrations/0006_auto_20170215_0948.py b/modoboa/relaydomains/migrations/0006_auto_20170215_0948.py
index 6f0ed989d..5f7ffd1ca 100644
--- a/modoboa/relaydomains/migrations/0006_auto_20170215_0948.py
+++ b/modoboa/relaydomains/migrations/0006_auto_20170215_0948.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.10.5 on 2017-02-15 08:48
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.utils.timezone
 
diff --git a/modoboa/relaydomains/migrations/0007_recipientaccess.py b/modoboa/relaydomains/migrations/0007_recipientaccess.py
index 4c86b5099..aa2f81198 100644
--- a/modoboa/relaydomains/migrations/0007_recipientaccess.py
+++ b/modoboa/relaydomains/migrations/0007_recipientaccess.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.10.7 on 2017-11-24 14:06
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/relaydomains/migrations/0008_auto_20171123_1653.py b/modoboa/relaydomains/migrations/0008_auto_20171123_1653.py
index e92b8e3af..1bc2fdda2 100644
--- a/modoboa/relaydomains/migrations/0008_auto_20171123_1653.py
+++ b/modoboa/relaydomains/migrations/0008_auto_20171123_1653.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.10.7 on 2017-11-23 15:53
-from __future__ import unicode_literals
-
 from django.db import migrations
 
 
diff --git a/modoboa/relaydomains/migrations/0009_auto_20171124_1508.py b/modoboa/relaydomains/migrations/0009_auto_20171124_1508.py
index 2c4a0f9c7..11e03c988 100644
--- a/modoboa/relaydomains/migrations/0009_auto_20171124_1508.py
+++ b/modoboa/relaydomains/migrations/0009_auto_20171124_1508.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.10.7 on 2017-11-24 14:08
-from __future__ import unicode_literals
-
 from django.db import migrations
 
 
diff --git a/modoboa/relaydomains/migrations/__init__.py b/modoboa/relaydomains/migrations/__init__.py
index baffc4882..e69de29bb 100644
--- a/modoboa/relaydomains/migrations/__init__.py
+++ b/modoboa/relaydomains/migrations/__init__.py
@@ -1 +0,0 @@
-from __future__ import unicode_literals
diff --git a/modoboa/relaydomains/models.py b/modoboa/relaydomains/models.py
index 5e3700c78..8e20b225c 100644
--- a/modoboa/relaydomains/models.py
+++ b/modoboa/relaydomains/models.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Relay domain related models."""
 
-from __future__ import unicode_literals
-
 from django.db import models
 
 
diff --git a/modoboa/relaydomains/postfix_maps.py b/modoboa/relaydomains/postfix_maps.py
index 77c5904e0..074ba9e97 100644
--- a/modoboa/relaydomains/postfix_maps.py
+++ b/modoboa/relaydomains/postfix_maps.py
@@ -1,10 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Map file definitions for postfix."""
 
-from __future__ import unicode_literals
-
-
 class RelayDomainsMap(object):
 
     """Map file to list all relay domains."""
diff --git a/modoboa/relaydomains/serializers.py b/modoboa/relaydomains/serializers.py
index 8887f2714..26cfbede1 100644
--- a/modoboa/relaydomains/serializers.py
+++ b/modoboa/relaydomains/serializers.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """RelayDomain serializers."""
 
-from __future__ import unicode_literals
-
 import json
 
 from django.utils.translation import ugettext as _
diff --git a/modoboa/relaydomains/tests.py b/modoboa/relaydomains/tests.py
index ca828e5ce..2c610814c 100644
--- a/modoboa/relaydomains/tests.py
+++ b/modoboa/relaydomains/tests.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """relaydomains unit tests."""
 
-from __future__ import unicode_literals
-
 import json
 
 from django.core.files.base import ContentFile
diff --git a/modoboa/relaydomains/transport.py b/modoboa/relaydomains/transport.py
index 641b66897..8c1c77aeb 100644
--- a/modoboa/relaydomains/transport.py
+++ b/modoboa/relaydomains/transport.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Transport backend definition."""
 
-from __future__ import unicode_literals
-
 from django.utils.translation import ugettext_lazy as _
 
 from modoboa.transport import backends
diff --git a/modoboa/relaydomains/urls_api.py b/modoboa/relaydomains/urls_api.py
index 56b3562b1..e11e61e64 100644
--- a/modoboa/relaydomains/urls_api.py
+++ b/modoboa/relaydomains/urls_api.py
@@ -1,14 +1,10 @@
-# -*- coding: utf-8 -*-
-
 """Transport API urls."""
 
-from __future__ import unicode_literals
-
 from rest_framework import routers
 
 from . import viewsets
 
 router = routers.SimpleRouter()
 router.register(
-    r"relaydomains", viewsets.RelayDomainViewSet, base_name="relaydomain")
+    r"relaydomains", viewsets.RelayDomainViewSet, basename="relaydomain")
 urlpatterns = router.urls
diff --git a/modoboa/relaydomains/viewsets.py b/modoboa/relaydomains/viewsets.py
index 8f75e266b..d7de1b82d 100644
--- a/modoboa/relaydomains/viewsets.py
+++ b/modoboa/relaydomains/viewsets.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """RelayDomain viewsets."""
 
-from __future__ import unicode_literals
-
 from rest_framework import viewsets
 from rest_framework.permissions import DjangoModelPermissions, IsAuthenticated
 
diff --git a/modoboa/test_settings.py b/modoboa/test_settings.py
index 535b8c3c1..0ad16752e 100644
--- a/modoboa/test_settings.py
+++ b/modoboa/test_settings.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 import os
 
 # Database
diff --git a/modoboa/transport/__init__.py b/modoboa/transport/__init__.py
index 96b626725..ba19ffc3c 100644
--- a/modoboa/transport/__init__.py
+++ b/modoboa/transport/__init__.py
@@ -1,5 +1 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 default_app_config = "modoboa.transport.apps.TransportConfig"
diff --git a/modoboa/transport/apps.py b/modoboa/transport/apps.py
index 7d27b0001..5beae6d6d 100644
--- a/modoboa/transport/apps.py
+++ b/modoboa/transport/apps.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 from django.apps import AppConfig
 
 
diff --git a/modoboa/transport/backends.py b/modoboa/transport/backends.py
index dc2ae5500..b6923b16d 100644
--- a/modoboa/transport/backends.py
+++ b/modoboa/transport/backends.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Transport backend."""
 
-from __future__ import unicode_literals
-
 from django import forms
 from django.core import validators
 from django.utils.translation import ugettext_lazy as _
diff --git a/modoboa/transport/constants.py b/modoboa/transport/constants.py
index b1786c081..80c50d66b 100644
--- a/modoboa/transport/constants.py
+++ b/modoboa/transport/constants.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Transport constants."""
 
-from __future__ import unicode_literals
-
 PERMISSIONS = {
 
 }
diff --git a/modoboa/transport/factories.py b/modoboa/transport/factories.py
index 7e08e0b34..332bd400a 100644
--- a/modoboa/transport/factories.py
+++ b/modoboa/transport/factories.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Transport factories."""
 
-from __future__ import unicode_literals
-
 import factory
 
 from . import models
diff --git a/modoboa/transport/forms.py b/modoboa/transport/forms.py
index 9309e0413..9d7ec1787 100644
--- a/modoboa/transport/forms.py
+++ b/modoboa/transport/forms.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Transport forms."""
 
-from __future__ import unicode_literals
-
 from django import forms
 
 from . import backends, models
diff --git a/modoboa/transport/handlers.py b/modoboa/transport/handlers.py
index 455b1030b..cb4e3f44c 100644
--- a/modoboa/transport/handlers.py
+++ b/modoboa/transport/handlers.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Transport handlers."""
 
-from __future__ import unicode_literals
-
 from django.db.models import signals
 from django.dispatch import receiver
 
diff --git a/modoboa/transport/migrations/0001_initial.py b/modoboa/transport/migrations/0001_initial.py
index 771b6a1ad..cd34ad3bd 100644
--- a/modoboa/transport/migrations/0001_initial.py
+++ b/modoboa/transport/migrations/0001_initial.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.10.7 on 2017-11-24 11:16
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 import jsonfield.fields
diff --git a/modoboa/transport/migrations/0002_auto_20180928_1520.py b/modoboa/transport/migrations/0002_auto_20180928_1520.py
index af5a49641..c44052197 100644
--- a/modoboa/transport/migrations/0002_auto_20180928_1520.py
+++ b/modoboa/transport/migrations/0002_auto_20180928_1520.py
@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.11.15 on 2018-09-28 13:20
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 
 
diff --git a/modoboa/transport/models.py b/modoboa/transport/models.py
index 0db5e59cf..e92166f21 100644
--- a/modoboa/transport/models.py
+++ b/modoboa/transport/models.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Transport models."""
 
-from __future__ import unicode_literals
-
 import jsonfield
 from reversion import revisions as reversion
 
diff --git a/modoboa/transport/postfix_maps.py b/modoboa/transport/postfix_maps.py
index a756fd57d..0be6fdcc2 100644
--- a/modoboa/transport/postfix_maps.py
+++ b/modoboa/transport/postfix_maps.py
@@ -1,10 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Map file definitions for postfix."""
 
-from __future__ import unicode_literals
-
-
 class TransportMap(object):
     """A transport map."""
 
diff --git a/modoboa/urls.py b/modoboa/urls.py
index e8fe24b79..082da04f8 100644
--- a/modoboa/urls.py
+++ b/modoboa/urls.py
@@ -1,7 +1,3 @@
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
-
 from functools import reduce
 
 from ckeditor_uploader import views as cku_views
diff --git a/modoboa/urls_api.py b/modoboa/urls_api.py
index ea1770cda..6c223f539 100644
--- a/modoboa/urls_api.py
+++ b/modoboa/urls_api.py
@@ -1,9 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """External API urls."""
 
-from __future__ import unicode_literals
-
 from django.conf.urls import include, url
 
 from modoboa.core.extensions import exts_pool
diff --git a/mysql-requirements.txt b/mysql-requirements.txt
index 8786ce81c..ea498b097 100644
--- a/mysql-requirements.txt
+++ b/mysql-requirements.txt
@@ -1 +1 @@
-mysqlclient<=1.3.99
+mysqlclient<=1.4.99
diff --git a/requirements.txt b/requirements.txt
index eb80cd838..5f09d4a98 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,24 +1,23 @@
 django>=1.11.8,<=1.11.99
-django-braces==1.11.0
-django-ckeditor==5.2.2
-django-reversion==2.0.12
+django-braces==1.14.0
+django-ckeditor==5.8.0
+django-reversion==3.0.5
 django-subcommand2==0.1.1
 django-xforwardedfor-middleware==2.0
 
 dj-database-url
 
 coreapi==2.3.3
-coreapi-cli==1.0.6
-djangorestframework==3.7.3
+coreapi-cli==1.0.9
+djangorestframework>=3.9,<3.10
 
-# bcrypt requires libffi-dev
-bcrypt==3.1.4
-dnspython==1.15.0
+passlib==1.7.2
+bcrypt  # Requires libffi-dev and python-dev
+
+dnspython==1.16.0
 feedparser==5.2.1
 gevent==1.4.0
-ipaddress; python_version < '3.3'
 jsonfield==2.0.2
-passlib==1.7.1
 Pillow  # Optional dependency for django-ckeditor
 progressbar33==2.4
 py-dateutil==2.2
@@ -27,5 +26,4 @@ pytz
 requests
 rfc6266
 lxml
-backports.csv; python_version < '3'
 chardet
diff --git a/setup.cfg b/setup.cfg
index 6f8d0cca9..427c34916 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,6 +1,3 @@
-[bdist_wheel]
-universal = 1
-
 [isort]
 atomic = true
 combine_as_imports = true
diff --git a/setup.py b/setup.py
index 6acb51e3b..fba4f5548 100644
--- a/setup.py
+++ b/setup.py
@@ -1,5 +1,4 @@
 #!/usr/bin/env python
-# -*- coding: utf-8 -*-
 
 """
 A setuptools based setup module.
@@ -8,9 +7,6 @@ See:
 https://packaging.python.org/en/latest/distributing.html
 """
 
-from __future__ import unicode_literals
-
-import io
 from os import path
 
 try:
@@ -42,7 +38,7 @@ if __name__ == "__main__":
         path.join(HERE, "postgresql-requirements.txt"))
     LDAP_REQUIRES = get_requirements(path.join(HERE, "ldap-requirements.txt"))
 
-    with io.open(path.join(HERE, "README.rst"), encoding="utf-8") as readme:
+    with open(path.join(HERE, "README.rst")) as readme:
         LONG_DESCRIPTION = readme.read()
 
     setup(
@@ -60,12 +56,10 @@ if __name__ == "__main__":
             "Intended Audience :: System Administrators",
             "License :: OSI Approved :: ISC License (ISCL)",
             "Operating System :: OS Independent",
-            "Programming Language :: Python :: 2",
-            "Programming Language :: Python :: 2.7",
             "Programming Language :: Python :: 3",
-            "Programming Language :: Python :: 3.4",
             "Programming Language :: Python :: 3.5",
             "Programming Language :: Python :: 3.6",
+            "Programming Language :: Python :: 3.7",
             "Topic :: Communications :: Email",
             "Topic :: Internet :: WWW/HTTP",
         ],
@@ -76,6 +70,7 @@ if __name__ == "__main__":
         scripts=["bin/modoboa-admin.py"],
         install_requires=INSTALL_REQUIRES,
         use_scm_version=True,
+        python_requires=">=3.4",
         setup_requires=["setuptools_scm"],
         extras_require={
             "ldap": LDAP_REQUIRES,
diff --git a/test-requirements.txt b/test-requirements.txt
index 2b7bf52d0..213307c99 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -1,6 +1,5 @@
 argon2-cffi>=16.1.0
 factory-boy>=2.4
-mock==2.0.0; python_version < '3.3'
-httmock==1.2.5
-testfixtures==4.7.0
+httmock==1.3.0
+testfixtures==6.10.3
 tox
diff --git a/tests.py b/tests.py
index 5177a3ec3..d34d331d3 100644
--- a/tests.py
+++ b/tests.py
@@ -1,6 +1,3 @@
-# coding: utf-8
-from __future__ import unicode_literals
-
 import os
 import tempfile
 import unittest
diff --git a/tox.ini b/tox.ini
index 523669065..acb3a43a4 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist = py{27,35,36,37}
+envlist = py{35,36,37}
 
 [testenv]
 changedir = test_project